Bloxorz

You control a block that's twice as tall as it is wide, and the only way to finish a level is to tip it end over end until it drops straight down into a hole that matches its width exactly. Roll it onto a tile edge-first instead of flat and it falls off the board, which happens more than you'd like at first. The isometric view makes distances tricky to judge, so a lot of the challenge here is spatial rather than logical. Levels get longer and the paths narrower as you progress, leaving less room for a wrong tip.