Assasin 1 & 2
I recently played all the ZZT games made from 1991 to at least the end of 2003, maybe beyond - nearly two thousand games in all. Of those I have selected just 66 to be included in my list of "best ZZT games ever." The sequel adds nothing to my review here, and is not included in the list.
To sum up ASSASSIN, because by itself it is not worth playing except as an object lesson:
On every board, you defeat some enemies. Having defeated them, you approach the black knight, who first insults you, then disappears. Not every game should follow a formula, but certainly more games should.
A formula gives a game a heartbeat. It pushes life through the game, but it is not what makes the game alive. You can give a heartbeat to an imbecile or a boring man and he still will not entertain you, but a game is always on the verge of disaster without some kind of recognizable repetition to keep the player grounded.