Newt Lift

Raise stepping-stones, hop for flies, then reuse the block that sinks behind you. Three exact-height catches and one spring leaf make every crossing a choice. Build mode adds one block to another lane. Hop mode moves one lane; the landing must be nonempty and within one level of your current height. Departing refunds one block. Spring permits a two-lane hop but is consumed on any armed successful hop; tap it again to cancel freely. Catch flies in order at lane1 height2, lane5 height3, lane3 height4.26 actions total. Falling into empty water ends the run; Undo recovers. Out-of-range and wrong-height hops are rejected freely.