Crunchy
Crunchy is a common word in roleplaying gamer slang; it has several meanings. Its opposite is Squishy.
• A game, game system, or aspect of either which requires complex math and/or is excessively detailed. For example, the infamous GURPS vehicle creation system. Comes from the term crunch.
• A character, monster, or NPC which is notoriously hard to kill.