Where can I get Pop?
For those who get stuck, a walkthrough by Foxman is also available.
Also take note that the game contains a programming error that must be fixed in order to obtain the secret ending, and a possible bug preventing the game from being completed in general which can be gotten around by typing "ZAP" at the cheat prompt (activated with the ? key).
Released: Aug. 22, 1998
Pop was Tucan's ZZT hit of the Summer of 98. An adventure game with tricky puzzles taking place in an environment I'd best describe as magical-surrealism. Like Deep December, it's a game with a lot of atmosphere, in this case taking place in a large tower on a tiny island in another dimension. The game was well received in its day, and went on to win a Game of the Month Award. It was also tucan's last ZZT release, though nothing indicates that it was necessarily intended to be such.
The game's text file describes Pop as a homage to ZZT's older days (it was only 7 at the time!), being inventory based and Kudzu-esque, and "a really sucky way to kill a few hours".
(Kudzu was another ZZT adventure where you mostly interacted with strange and usual people and things to solve puzzles)
The game's title screen opens with a flashing message on the bottom of the screen explaining that Pop is a game where you need no bullets or brain, and credits the game with a second author known as kabra-corn. I've never heard the name kabra-corn anywhere other than this game, and whoever this other person was, there's no clear remnants of them in ZZT's history today.
Upon starting the game, the player is taken to a menu of sorts. Lots of games opted to start on a menu rather than jump right into the game itself to allow for things like skippable introduction boards, credits, or game instructions that the player may or may not be interested in.
Tucan was nice enough to give some information about himself at the time of making the game. Thank goodness we no longer have to deal with preps with pagers in the 21st century. There's nothing too revealing here, just a typical teenager with ZZT as a unique outlet for creativity.
As is often the case, credits in ZZT games are just the author listed for everything except for the special thanks section. The mysterious kabra-corn goes uncredited on this screen. Several of the credited names list the other games which directly inspired Pop's creation.
There's also a shoutout for #darkdigital, which was the main ZZTer IRC channel at the time, which was hosted on AustNet despite the vast majority of ZZTers being from North America and Europe.
I also love the promise of writing down the music that was listened to during the creation of the game. Listing what CDs were listened to, and what food was eaten became a common thing to include in the credits for 24 Hours of ZZT contest entries. This is the first I've seen it done in a regular game.
There's an inaccessible board in the game's file which does list this music. It includes Beck, Jimi Hendrix, and The Velvet Underground among a few others.
The last menu section to explore is the information on the game itself, what its goals were, how its name came to be, and lastly an explanation of the game's inventory system
And about that inventory. ZZT doesn't have any innate inventory system beyond keeping track of ammo, torches, gems, and keys. However, by turning ZZT's cheats into a gameplay feature it was possibly to loosely recreate the sort of thing you'd expect from a classic LucasArts or Sierra adventure.
Typing a ? during gameplay in ZZT opens up a cheat menu, and +>flag< could be used to set a flag. On every single room in the game an object checks in a loop if the flag "i" is set, and if so, it opens a list of items you have, allowing you to select one to use on whatever you're standing next to.
The ?+i system was used in several ZZT games (and a few action games would have you reload a gun with ?+r), but was relatively uncommon. Actually typing the command got tedious quickly, and if you made a mistake and typed ?+o instead, you'd set another flag and have to clear it with ?-o.
ZZT only supports 10 flags, so games which used this system had to make sure you never got more than 9 items at a time (as the 10th was needed for the "i" flag itself), and would have their flow designed around which items you might still have. If an 11th flag was set, it would overwrite the 10th flag, leaving you stuck with a now missing item.
Let's take a look at how the code is structured for such a game with this new ZZT scroll technology
#if i inventory
#if r !r; a rock.
#if s !s; a stick.
that's probably not it.
• • • • • • • • •
You can see that the inventory code checks for more flags and if they're found brings up an interactive hyperlink the player can select which jumps to the :r or :s labels to use them. From there, #all:rock will tell every object on the board that if they have a :rock label in their code to jump to it. For objects that don't, nothing happens and they continue executing the code they've been running already.
If an object has a :rock label, it then tells the inventory object to jump to the :loop label and then does whatever it does when you try to use a rock on it. If nothing tells the inventory to jump back to :loop, it will go through it's /i statements which tell it to idle for a cycle, and eventually hit #stupid, jumping itself to the :stupid label and letting the player know that whatever they tried didn't do anything.
It's a cool little engine that shows what sort of mindset you need to have to write ZZT-OOP. You're constantly sending label jumps to other objects back and forth and reacting to that.
Of course, in most cases the thing you're interacting with is right next to the player to begin with and you could just have the player touch it and bring up a list of items to use on it there, but that's not nearly as flashy.
With the game's mechanics explained, it's time to actually play some Pop!
The player is dropped in atop the lavender tower with an empty inventory next to an art piece consisting of four globes, three of which have notches in them. One of those notches has been filled with clay. This piece is known as the ya'yono vekka, as displayed in the corner of the screen.
In Pop, every board has a title which is displayed to the player in a corner somewhere. It's a nice way to help the player navigate the tower, giving a concrete way to reference any room no matter how abstract its design may be.
With only one way to proceed, the player heads to the outside of a library. There are some plants in the corner which do nothing, but are internally named as plants. I assumed it was some sort of debris in this case. The sign also states the entrance leads to a library and the player comments on being surprised to find it written in English.
Inside the library is the game's first lore dump. Pop has quite a lot to read from books as a method of world building, and suffers from a case of telling rather than showing, but reading through everything you find does help you make sense of future puzzles and gives a lot more insight into the dimension the player's been trapped in.
Talking with the person that's busy reading offers no help, as they're too invested in their book to bother speaking with the player.
Several books line the shelf, and you can read every last one of them. Don't feel obligated to read them top to bottom here. Though important in actual gameplay, they can definitely be skimmed here.
The mythology book is a bit meaningless. I'm not sure if a nimby is a Not In My Back Yard. "Yapok" is a name drop of the ZZT game Yapok Sundria.
the tower - by keykeeper val'h'ruhai.
the lavender tower is a small universe
consisting of exactly one sea, one sky
one island, one very large tower, and
a large amount of fuck-ups. as king
otto xxvii (most revered) once said,
"the lavender tower's base is basically
the well-known principle that every
great plan, at one point, must either
fuck, or be fucked."
basically, the tower is some sort of
divine joke created by the big guy
upstairs. it is utilized by some of
the higher beings, whether these
beings are demons or angels, it is yet
to be seen.
it is a well known fact that the lavender
tower serves as a sort of trap, if you
will, for people from other dimensions.
however, the trap is a very selective one,
and will only capture people of its own
preference, that is to say, young men
and women of a very curious persuasion.
why these particular men and women
are selected remains unexplained, but it
is said that the demons/angels are testing
the proportions of human curiousity and
another strange fact about the lavender
tower is that at no point does it open
out onto the ground level. in fact, a
floor or staircase situated on ground
level is yet to be found by the several
"wanderers" who "wander" about the lav-
ender tower in search of an exit. not
even the keykeeper of the lavender tower
has found an exit. which leads us to
the keykeeper of the tower is a god-like
figure that watches over the "wanderers",
and tends the grounds of the lavender
the keykeeper of the tower is a former
"wanderer" selected by a small ring of
unseen "watchers", the demons/angels
who constantly glare at the tower
denizens from above. i have had the luck
to be selected for this sole privelege,
it came to me as a dream. the
"watchers" informed me that i had attained
a very remarkable amount of curiousity,
a feat that would not go unrewarded. i
woke from this dream, breaking out in a
sweat, with a key around my neck.
of this affair, i can tell you no more,
other than that it is true... the key-
keeper of the tower does attain the
position of a demi-god, if you will.
there is nothing that is not outside of
hûdû- a large possum-like creature with
fierce territorial instincts. they
can speak all or most languages,
possessing both a tenacity to
learn and a fiery intellect.
however, the hûdû is not without
its faults. it is surprisingly weak,
very belligerent, and usually un-
willing to speak to anything about
grook- a furry, mammalian/snake. these
creatures can detect the presence
of minute amounts of gold.
they served keykeepers as a metal
detector of sorts. they are now in
scarcity, a fact owing to their
magnificent golden pelts. as otto
the xxvii described: "a sort of
rankallan- a large scaly lizard type
creature possessing suckered
feet, and over 20 feet of
colorfully decked body.
rankallans lead long peaceful
lives consisting mainly of
eating passing "wanderers"
and scaling the tower sideways
with suckered feet. they re-
produce asexually, so there is
usually only one rankallan in
existence at a time. the cur-
rent rankallan answers to the
name of boris. rankallans, when
near death, all go to a local
cave to die. the remains of a
slain rankallan are perfectly
preserved near the tower
phrog- a creature resembling a colorful
bullfrog. it is well known that
they are extremely partial to
mangoes and will come out of
hiding places just for the cause
of one. their hides are tough,
and it will take more than one
slash of a knife to kill a phrog
and take its hide. their hides,
which are indeed decorative, are
also poisonous, and are tra-
ditionally used on blowpipe darts.
reazles- small, rat/weasel combinations.
a reazle's chief predator is a
large slice of gouda or stilton.
they are known to eat coins them-
eguinius- large, predatory sea-horses that
dwell on land and water. it is
a well-known fact that eguinius'
trample victims to death with
their groins, then slowly suck
their juices through straw-like
eboral- leathery combinations of
loch ness monsters/hammerhead
parakeets- the one animal known to exist
in all universes at the same
time, for some annoying reason.
parakeets have the ability to
memorize long phrases like
"help! jonathan's locked me in
the closet!", and release them
when jonathan's having tea with
otters- not like the otters found in
similar universes. small, sleek,
sentient creatures known to
breathe fire and eat things dwell-
ing in closet. the first keykeeper
moe was known to worship these.
druphus- adorable rabbit like creatures
who were trained by king otto
the xxvii to eat people who said
the phrase, "gee, otto, i'd
really like to borrow some cash."
octarines- not animals, but fruits.
octarines have a nectarine-
like appearance and a blue-ish
color. they are known to taste
like an individual's conscience
(curious people taste a curious
octarine, mad people taste,
strangely enough, a mad
octarine.) rare delicacies.
chameleon rocks- are known to change
colors to blend into
their surroundings to
survive people who,
after devouring a
feel like devouring a
• • • • • • • • •
The second book gives the necessary backstory for the game. In short, curious creatures are taken from their dimension to this one where mysterious "watchers" are entertained by those who search the tower for an escape. A keykeeper title is given to those who show an especially noticeable amount of curiosity, essentially putting them in charge of the tower's upkeep. Nobody has ever found an exit, and nobody has been to the tower's ground floor.
The second book also goes on to describe the creatures found within the tower. This is less of an information dump, and more of hints on how to solve some of the puzzles later on with some sillier entries for humor as well.
The last book is a sixteen page diary by Jenner, the tower's 10th and current keykeeper.
july 1, 1997 - have arrived here, rather
inexplicably with my dear dear friend, il-
sa magras. i have spoken to the locals,
and they say that this universe serves
as a trap for people of a curious nature.
the 'watchers', the angel-demons, watch
over us from afar, running tests and bets
and whatnot, and sooner or later, they
kill us off one by one. well, not 'kill',
adrian said (adrian is a dark cyan blob
we met today), those in question just sort
of disappear. they say that once you find
the exit, that's it. the 'watchers' finish
you off. cruel existence. how can we *not*
keep searching for the exit? i told ilsa
we must have faith.
july 10, 1997- these grounds are quite
large, but there seems to be no way
down to the bottom. all of us appear
near a statue called the ya'yono vekka,
a mysterious set of globes, some with
notches carved into them. i accidentally
got my walking staff stuck into one of
them, and it doesn't seem to want to come
july 12, 1997- tried catching some of the
phrogs in the groves. it seems they
favor mangos. they are highly susceptible
to knife-stabs, as adrian demonstrated.
they make terrible eating, but as adrian
also demonstrated, needles can be rubbed
against their caustic hides to produce
july 13, 1997- i noticed that the hûdû in
the grove steps on the exact same branch
on his way down. i am currently devising
a plan to rid him of that ghastly
rajaijah shroom, the shroom of madness.
july 14, 1997- nearly got stabbed to death
by assassins who offered me lunch. they
congratulated me for outwitting them, and
thus, gave me several clues to the finding
of the exit.
july 16, 1997- i won a gem by doing
battle with a mutant reazle. at first,
i had no clue what purpose the gem served,
but the reazle told me that i would need
at least 8 of those to find the secret
ending to the game. i asked him what
did he mean by 'game'? how could this
universe be a 'game'? and there was a
secret ending to it? come now, how can
one already foresee the ending? the reazle
disappeared. i hid the gem inside the ya'
july 20, 1997- ilsa and i have found a new
staircase! we have no clue where it leads
to, but we have decided to keep it a
secret from the rest of the group.
july 22, 1997- i have lost ilsa. we found
the exit, it appeared as a shimmering
gateway that was approachable from any
side. ilsa urged me to step through, but
i refused, i did not know where it would
lead. this universe is fine enough for me.
ilsa stepped through, and the gateway
closed behind her. she is the only human
to ever find the exit.
july 21, 1997- i had staked myself out
where the gateway once was, when people
garbed in strange manner came up to me.
they were watchers they said, and said
that they would like to reward me for my
courage. i had no courage, i denied, but
they said that true courage comes from
squelching one's inhibitions. no, i said,
true courage comes from doing what one
thinks is right. a 'watcher' named boris
laughed and said that we need not lessons
in morality. they have crowned me the new
keykeeper. don't let the name fool you.
all i do is maintain this place. they
will tell me more about this universe
lost the date.
i just realized these stupid watchers had
not known that ilsa was with me. they had
thought that i was the only one. just as
well, if they had known, they would've
boris explained to me this dimension. it
does not travel. when another dimension
is adjacent to it, this dimension overlaps
the other. if a sentient being happens to
be on the exact point of overlap, and this
sentient being is an inquisitive sort, he
is sucked through into this one.
had an argument with boris over whether it
was right to kill the more successful ones
the ones that actually found the exit and
used it. it makes the rest of the
wanderers fearful. most of the wanderers,
especially adrian, despise me for some
i have built a vacuum cleaner for the
watchers. they are especially pleased with
it, in their pocket dimension, they have
no such minds as mine, the mechanical
mind. they say that i should start build-
ing more for them.
boris explained to me that this dimension
is actually a game, made by invisible
outsiders for enjoyment. the watchers say
that they have never seen these
ur-watchers. i find it humorous. watchers
boris said that the purpose of this game
is to be killed by watchers while trying
to find the exit. i find *that* futile.
is dying considered winning? but if one
wanders around this dimension for an
eternity, have they won the game?
boris has given me plans for a device
he could not explain. i looked at them.
they are brilliant. i will not tell the
watchers, but i have devised a way from
these plans to make an escape route
for myself. a simple catapult, that will,
if you will, catapult me into an adjacent
dimension. all or nothing. ilsa has
written me several letters that somehow
flew into this one. this gives me reason
to believe that my home dimension is
bloody work. i had to kill a rankallan
that ate too many wanderers. the plumbing
in the men's bathroom went out. i can't
find the glyph that opens the laboratory,
i left it in the soap factory. reazles
have overtaken the gallery. these mundane
subjects distract me from my major ob-
jective. and the interdimensional workman
has just delivered an exquisite painting
have finished the transdimensional cata-
pult. it is done.
• • • • • • • • •
The keeper's diary in interesting as it drops so many hints for the game's puzzles that it's very much like its own subtle walkthrough for much of the game. To summarize, jenner and isla were brought to the tower together, and actually managed to find the exit. Isla ran out and jenner stayed behind, having grown tolerant of life in the tower's dimension. Eventually one of the watchers discovered jenner and made them the new keykeeper. Upon learning that exiting normally means certain death, and that an alternate means of exiting safely could be created jenner planned their escape.
Continuing deeper into the library brings the player to a large bookshelf. The use of half solid characters in varying colors like this was a very common way to create bookshelves. In a bit of an issue with continuity, the player immediately comments on not being able to find a dictionary, but no dictionary has been mentioned, until investigating the torn out pages of a diary in the corner.
The player is thus informed about a dictionary that will let them communicate with those who only speak izanuoylrak'ian. It also provides a bit of insight onto the ya'yono vekka seen at the start of the player's journey. This diary also reiterates the importance of the eight gems which can be found in the game in order to obtain the special ending.
As we'll see, obtaining the eight gems without using a walkthrough or peeking in the editor is a gargantuan task. Even Foxman who wrote the game's walkthrough admitted to not knowing where one of the gems is. I'm confident that nobody got the secret ending without cheating in some way.
In order to find the dictionary, it may be wise to ask the librarian for some help.
you come up to the librarian and he greets
you in izanuoylrak'ian:
you: hello... i... uh...
you: izanuoylrak... yes? yes?
you (thinking): good... i think he under-
stands *that* much... what's this? it
seems he wants a trade...
he wants a mango for a measly dictionary?
where the hell do i find a *mango*?
• • • • • • • • •
And with that the player gets their first task. Find a mango, receive a dictionary. The back of the library contains nothing of interest, just a few open books on a shelf. It's time to move on down the tower.
The southwest tower board foreshadows some lower balconies that the player will eventually be able to explore. On the current level, there's a large shrub and a creature standing near it.
One thing worth pointing out here, is the interesting shading on the tower displayed here. It uses the standard ZZT fade of solid -> normal -> breakable -> water -> repeat which is used normally in the skyline in the background, but on the tower itself it's handled a little differently. There are these sort of vertical seams created which help add some roundness to the shape of the tower. This is done by taking advantage of how normal walls and water tiles are the inverse of each other graphically. So a dark purple on dark blue normal looks almost but not exactly like a dark blue on dark purple water. This creates the seam when you put the two next to each other and is a really cool effect that I don't think I've seen used anywhere else in this manner.
The entrance to the main hub of the tower is the next screen. This room also has the first solvable puzzle, and immediately requires you to get into Pop's mindset. The game's included text file even tells you how to solve it, which is generous because it's already not the most intuitive solution.
Investigating the statue brings up a few interesting choices of what to do to it. You can go down the list and get various reactions, but until you insult it enough, it won't do anything. ZZT games rarely required repeated interactions like this so even just getting the statue to wake up can be a challenge. And when it does, you begin a fortunately slow chase.
With the statue slowly chasing the player, they'll have to move over to a large drill, activate it, and lure the statue to its demise. All of this is a very elaborate method of obtaining a rock. The player can also activate the drill in advance, but the statue does move slowly enough that it's not necessary to pace back and forth across the board for added safety.
Murder count: 1
Rather than proceed inside the tower, I continued down the path. There's a lot to take in on this board. Like the dead body! But first let's get ourselves killed by a coke machine.
Yes, a second game with coke machines in it. Unlike Deep December's commitment to brand ideals, in the world of Pop, vending machines can be far deadlier.
You can safely spit in it though.
Next in line is a parakeet. Just like the statue and coke machine there's a variety of options to choose from.
Talking to the parakeet makes the dead body up ahead go from suicide to murder. Attempting to kill the parakeet yourself is met with a message about how it refuses to give you the chance. You're also unable to offer it any food regardless of what's in your inventory.
Offering it a gem which you don't have will cause it to fly away, which it actually does by moving up and across the screen to the edge before disappearing, which is a pleasant detail rather than simply making the object #die and vanish on the spot.
If the player does have a gem, the parakeet will take it before leaving, thus preventing the special ending from being possible. It's a pretty needless design decision.
The victim is revealed to be a maid, and the circumstances of her death are mysterious, but will ultimately go unexamined in the player's quest for the exit.
The last board of the tower's exterior is the guava groves. This board has quite a bit to interact with despite its small accessible area.
Firstly is the goal of the dictionary quest, a mango on the tree. Unfortunately there's no way to remove it currently.
Next is this viewing lens. Without any gems there's not really anything the player can do with it yet either.
Attempting to pick the mushroom causes the hûdû atop the tree to run down and bite you for trying to steal their mushroom. So we are 0 for 3. What a productive trip to the guava groves. Time to backtrack and enter the tower proper.
The board has a really cool perspective, simultaneously showing both the inside and outside of the tower. It uses transporters which blend into the walls to let the player transition from the outer section to the inner.
Talking to the gatehouse-keeper gives you a prompt to give him your name. Each option gets a slightly different response, but none of them have any effect on how the conversation proceeds.
so... anyways, my name's sir martin lugg,
for ye... been gatehouse keeper o' this
here tower for past sevendy nine years..
been ups and downs, lately. don't think
of yourself as the only bright eyed
young-un to come through these doors,
sniffing every crack...
sir lugg: that's it for ye... i've been
searching a way outta these damned
towers for years... it's all mazes and
sir lugg: do you?
sir lugg: zackly the point. people come
in, don't come out. firstmaster
jenner allus takes care of 'em. gives
em jobs, or 'e just takes 'em down
to the basement... they don't come up
from there either...
sir lugg: ain't no tale, sonny. it's real.
any case, jenner's a kind soul. 'e's
just a bit confused...
yes, son, confused. 'e built this place...
talked to me a spell or so... a long
while, tried to see things through
with me... said i was one of the smarter
ones... hell, he even told me i'd
be runnin' the place once he kicked back..
'e said it was a trap. y'know, the way
a spider web gets 'em chiggers, the
towers were meant to get curious folks
like yerself... never said what 'e'd
do to 'em, just said he liked company
of thinkers, then.
well, been nice talking to you... come
back sometime soon.
sir martin vendul lugg looks up
well, e'er since about two weeks ago,
those there mushrooms blocked up the
passage to the tower... vicious mushrooms.
ye'd best watch out for 'em.
izanuoylrak'ian. like from around the
heptagonal sea. it's hard to git, but
you can hold a conversation fer a spell
if you've got a dictionary...
i dunno, 'is face keeps changin'... one
thing, you'll recognize 'im by 'is eyes..
yes, them eyes...
one's justice. and one's the weasel...
yep... justice is blind, y'see, so
the weasel does the seeing, and justice
acts upon 'is eyes... rather unfair.
justice makes some mighty bad decisions
• • • • • • • • •
There's quite a conversation to be had with the gatekeeper. Again the dictionary is stressed as being something to get sooner rather than later. There's also the mention of the mushrooms blocking the actual entrance and the weasel that's been tricking justice.
This leads to the next puzzle. In order to balance justice's scales, something needs to weigh down the lighter one. This is where the rock from the statue comes in.
With the mushrooms gone, the player can now enter the tower, though two of the passages are blocked.
On the carpet at the entrance, is a large piece of cheese and a rat quite interested in it, but other than that there's no interaction between the two objects.
What might appear to be a passage on the painting is in fact an inscription, revealing it to be a painting by isla to jenner. Jenner's diary mentioned that isla had been able to send messages from their home dimension into the tower's since the two were aligned. The hint given here isn't readily apparent, but will come into play later.
It turns out if you look at the inscription a second time, you'll find out there's a note on the back of it which mentions that the two of them had a secret room in the library and that isla has a surprise there for jenner.
Some ZZT games would put passages on picture frames as a way to take the player to a board where they could view the painting and nothing else which is what I was expecting here. Using the same character as a passage for this object isn't the ideal choice, but there's no harm done here in expecting a passage and just getting a message instead.
The worker in the upper right has been waiting for jenner who hasn't been around and as is the theme with Pop, presents a variety of dialog options to the player.
drinking on the job, eh?
what exactly *does* that machine do?
how'd you get into this tower place?
the boss says it's break-time...
Telling the worker it's time for a break results in them rushing out of the room, taking the player along for the ride if they happened to be below the worker when they talked to him
When they leave, the passage sound effect plays! More fun little details.
With the worker gone, the player can now pick up a bottle of oil that was previously inaccessible. After doing so, I follow the path to the only new exit, the cafeteria.
The cafeteria has lots of people to talk with, most of which are pretty inconsequential.
you blink your eyes... a strange pulsating
creature stands here, looking passively
at the menus. yes, its quite possible for
a large, amorphous mass of snot to look
passively at something.
no, i... uh, thought... well... you kind
of blend into the walls when you stand
so, what universe are you from?
bob the blob, huh?...
sorry, it's a... uh... human joke...
no you're (you think better of it)...
The table in the top left has something a bit more meaningful.
yeah, i suppose so... i'm lost.
wait... these angels... uh... demons
locked you inside this tower?
Again the player is told that they need to give up in order to actually escape the tower. Bodhran the otter is constantly changing colors as well in this screen, so attention is easily drawn to them. But the most important conversation you can have in the cafeteria is with the person located in the lower right.
you: hello there.
you a new arrival here?
did you build this place?
do you help them?
any advice on getting out of this place?
but i've just started trying to get out of
these damned towers!
two dimensions? but that's impossible!
are they overlapping each other!
game? exits? what the hell are you talking
How much of the Pop's story is meant to be taken as metaphor and how much is actually breaking the fourth wall is purposely ambiguous. It's a ZZT game, but are the watchers actually aware it's a ZZT game?