how to summon creatures in divinity 2

Question

how do you summon a creature in divinity II?

Answer 1

The first creatures you can summon are ghosts and 'undead', you put points into the appropriate skill, drag the skill onto your quickbar at the bottom of the screen, and activate it by clicking or pressing the hotkey.

Your actual 'Creature' though is summoned using a Crystal Skull, you get this from a quest, and summon the creature in the same way as above, but by putting the Skull inventory item on your quickbar instead of the spell.