Sivion is arguably one of the biggest (size and length wise) ZZT games around. It's an adventure RPG, nearly 360kb in one ZZT file. It has a plot, which is actually slightly superfluous but serves nicely anyway. You are Rook, a nobleman exiled from the town of Gwin; after the death of your father, the mayor, your mother attempted to take over but spent the town's money badly- leading to a revolution leaving her stoned to death and you without a place to call home. However, you soon find yourself in another town, Bespin, and under an assumed identity you settle in a house you share with a friend called Dulcis. All seems well, until one day Aprithian assassins begin to show up around town for reasons unknown, and while running an errand for Jara you discover that Dulcis is not all that he seems to be...
For 1995, the graphics in this game are well done- plain by today's standards, but quite sufficent. There isn't much music (apparently the author can write it but doesn't like PC speaker sound much, and who can blame him), but what there is is quite decent; for some reason I especially liked the little beat played at the start of the game during the Mission:Enigma ripoff sequence. To this day it rings true in my mind! Gameplay is a defining factor of the game, too- it actually plays in the classic ZZT game format (ie. pre-programmed enemies, the occasional big boss object shootout), but does it in a distinctly medieval fantasy way (ruffians are assassins, lions are trolls, tigers are demons), and not all the enemies are pre-programmed.
Like any true RPG, what makes Sivion interesting is how 90% of the game is made up of side-quests which somehow tie into the bigger picture (ie. do x to get to y, and be rewarded with z). On your travels you'll save a man's fortunes from a malevolent djinn, defeat an evil Chthulu-style cult and steal from a bank vault in order to pay back a loan shark. All good family fun! Pretty much the first third of the game involves trying to get a poisoned needle, for exchange for strawberries from trolls, during which time you traverse mines and magic mazes and solve riddles to achieve what you require. Even after confronting the biggest boss of the game, don't be fooled into thinking you've won; even after this, you must infiltrate a castle, journey across a desert and other such excitements. The sprawling nature of the quests you undertake does lead to a disjointed feel to the game, but it's mostly fun (not included; those goddamned darkened, invisible mazes)- and isn't that the point of a game?
The one major downer I have on this game are the regular plugs for the MegaZeux version, which is apparently way cooler than the ZZT version with a more involved plot, better developed characters, more game etc. Don't bother looking for it because it doesn't exist, past a tiny little five screen demo made in MZX v1. So forget that, just be content with what DOES exist. Bottom line; if you can run it, play it- if you can't, go get a new computer you stupid cheapskate.
(ps. for those of you who can't run Fred! 2 due to its being even huger than Sivion, the password is BARNEY. You'll see what I mean.)