Thump

Thump is a Desert enemy with a brutally simple but highly inconvenient gimmick: it can only be damaged from behind. Its jump attack damages and displaces every unit it lands on while knocking back adjacent units, and it moves completely randomly, making it difficult to anticipate or position against. With 12 HP and movement 3, it is not exceptional in raw stats, but the back-only damage window turns every encounter into a positioning puzzle.

Attacks from the front, sides, or above deal no damage whatsoever. Thump's random movement means it can shift which direction it faces unpredictably between turns. It leaves no corpse on death. However, several specific abilities bypass the positioning requirement entirely: Become Entropy, Hyper Beam, Asteroid, Haunt, RNG Cannon, Reap, Giga Drain, Rebuke, Wrath of God, Split the Atom, Mega Blast, and others that target tiles directly or emit sparkle effects all deal damage regardless of facing.

The safest approach is to wait for Thump's random movement to expose its back, then strike immediately. Cats with high mobility can chase its rotation. If you have any of the exception abilities listed above, use them freely since they ignore the directional restriction entirely. Avoid bunching cats together — Thump's jump attack hits every unit on the landing tile and knocks back all adjacent ones, which punishes clustered formations severely.