Skull Warrior Value. The current value of the Skull Warrior in trading is 1.3k gems.If you want to get your hands on the shiny version of the Warrior, then you will have to fork over 28k gems instead.

Skull Warrior is a ground unit that deals a lot of damage and stacks Burn damage to enemies which is 30% of the base damage over three ticks. ... 28 Yellow Stars; 2 Rainbow Stars; ...

There will be a Yellow Skull here that once you interact with, it will cause the ceiling to come down. A little opening will pop up that will prevent you from being crushed if you get inside of it.