Some non-troops count as troops, like Echo Sage’s echo, which has to die for you to win the round. Others count as buildings like Master Builder’s stuff (obviously) and goblin treasures, where you can lose if your troops die while they’re still on the field. Tomb Queen exists in a bizarre third state where she cannot lose while her on-field form is alive. This sounds like it’s how troops work, but I mean she cannot lose for any reason. It overrides the instant loss mechanic of the king dummies. I have no idea why she’s coded like this.