Frustrating.
It makes you wonder whether the game testers actually bothered to play a single player game and whether they'd ever be able to actually complete a game by beating Motaro and Shao Khan. Cos I don't think they could do it.
Puzzle Kombat is good fun, but becomes similarly frustrating when trying to defeat the final character. But at least he/she feels beatable and the difficulty setting is not so far out of whack. Strangely, Puzzle Kombat starts off in the medium difficulty setting, while the main game doesn't offer such an option. It would definitely benefit from this, cos it feels like it starts out in ultra hard - but even ultra hard in Tekken is beatable. The default setting in Ultimate Mortal Kombat 3 should be named impossible, to be closer to the truth.
I imagine this game shines in multiplayer, but as a single player game it's hard to recommend given its insane difficulty setting and ultra-reactive AI.