Levels that seem impossible suddenly become simple, not because you've experienced a breakthrough but because the game has just changed the rules on a whim. Except when the game decides that it can.

It's established early on in the game that once a crate is in place it can't be moved. Unfortunately, alongside those moments of delightful clarity, Psychoban also has too many moments of furious frustration. Most of the levels are well designed, and the game has a slew of decent 'eureka' moments, when you finally work out which crate you have to slide where to complete a room. Multi-levelled rooms, tight corners, and problematic angles all mean you'll have to think carefully before you start your sliding. You can't drag crates, only push them, so getting them stuck in a corner means you'll have to start the level over or tap the 'undo' button to move yourself back a step. In each level there are a number of slots in the floor, and to make it to the next room you need to push one of the green crates into each of them.

Your job is to slide green crates around at the behest of a maniacal doctor and his strangely compassionate assistant. The game casts you in the role of a mental patient in a selection of creepy asylums. In some games, that's just part of the challenge. It likes to pull out the rug, turn out the lights, and then batter you with carpet beaters. It's as though the game has pulled the rug out from under you, and then laughed. Unless the game tells you otherwise, an action that works in one level should work in the next. Consistency is a spectacularly important part of any puzzle game.

Psychoban online