Dungeons 3

Done in the "Baptism of Fire" level. Midway through the level you'll be given the Grave Golem. It is extremely strong and tough so you should not have any difficulty keeping its health above 50%

The first time you fight with the Grave Golem, the Heroes drop a regen health spellbook, which if taken by the Grave Golem will make this trophy nigh impossible to miss. Due to clunky controls it can tricky to pick this spell book up as the game starts a wall of fire which slowly creeps towards you: you must keep moving ahead of it or lose the level immediately if Thalya is caught by the flames. To get this regen health spell book, you need to be quick with the fight and get ready for the Grave Golem to pick up the book once it's dropped.

If you have good control of Thalya and the Grave Golem, you should be able to keep the Golem's health above 50%. If you complete the level with the Grave Golem's health above 50%, the trophy will pop once the level completes.