Bob-Omb

Bonk: if this creature drops to half its hitpoints or less and is still living, then its bonk trait activates

Bonk Trait: Bob-Ombs retract their legs and become incapacitated, beginning a two round (starting from the first round they take after they are bonked)/10 second count down which, at the end of the count down, causes them to activate their Self-Destruct ability without taking an action. Bob-Ombs can also be bonked by an effect that makes them incapacitated.

Fire Susceptibility: If Bob-Ombs take fire damage, they immediately Self-Destruct with double the range, affecting everything within a 20-foot sphere that isn't behind half-cover or greater instead of a 10-foot sphere

Self-Destruct: As an action, this Bob-Omb can self-destruct, causing it to immediately drop to 0 hitpoints and cause a 10-foot sphere explosion radiating from itself that affects all creatures and objects that are adjacent to it and not behind half cover or greater. objects that are affected by it take 3d10 fire damage, and creatures must make a DEX saving throw of 15 or higher to dodge out of the way, otherwise they take 3d10 fire damage as well.