How chains work
One strike, many BONKs
A chain is every BONK one strike causes. Hammer modules add hammer BONKs around the strike, special moles react when they are hit, prizes and chemistry recipes add their own reactions. Each link pays base x chain step x Momentum tier.
Reactions hop about every tenth of a second, so you can read how the cascade travels.
Fuel and sparks
Normal moles are the fuel: a Tesla needs moles to arc to, a Bomb needs neighbours. Specials are the sparks. Shells block some links: stone ignores everything except your hammer, a helmet needs two hits.
Chemistry recipes link two pieces into a new behaviour; with both members mutated the recipe resonates.