Jewel Monsters
There's always a reason to match three or more similar objects together, but the semantics are just paperwork. This game tries to make matching more of an adventure by having us fight monsters with our matching powers. The more you think about it, the more you're focusing on things that just distract you from the game itself. There could be all sorts of reasons why these monsters are vulnerable to jewels being matched, but all that matters is that that's the reality. You need to think strategically and quickly because this is a puzzle game in the trenches with monsters bearing down on you.