Divinity: Original Sin 2 - Definitive Edition (EP)

Just some tips for if you're finding this fight hard - on Classic difficulty I just managed to beat it at level 10. Firstly, although it's tempting to focus on dealing physical damage to Andras since his physical armour is significantly weaker than his magical armour, he can cast bone armour and restore it every few turns. Focus on dealing magic damage to him, and as soon as possible, have a character with teleportation teleport the bone giant as far away as possible - he walks incredibly slowly so won't make it back to the fight for a few turns.

Stonegarden cemetery east of Driftwood. Andras will be guarding Qanna’s tomb. Easy fight if you’re level 11