Divinity: Original Sin - Enhanced Edition

This is one of 2 achievements that relating the the outcome of "The Troll's Bounty" quest, picked up from Brandon in Silverglen. The quest is exactly the same until you hand it in when you get the option to hand over or keep the tenebrium. For "You Keep Me Rockin'" you have to hand it over.

The best option, in my opinion, is to hard save before handing the quest in, complete this achievement, reload and complete "Truth be Told", as the reward for handing it over is far more important.

The earliest this can be completed is actually not linked to the Troll Lair, but instead the Mines.

Once you are making your way through the mines, you will trigger a waypoint (Luculla Mines - Chasm). Head down the slope here and at the end there is a tenebrium vein. Make sure that the person who mines it is holding the box given to you by Brandon. You can mine the vein 5 times, giving you 5 pieces of ore.

Towards the end of the mine. There is a room with some dormant Death Knights. Search around and you should find 5 other ores/bars of tenebrium. Giving you enough to complete the quest. Once again, make sure the character with the box picks them up.

Head back to Silverglen and before you speak with Brandon, make a hard save as there are two acheivements based on the choices presented in the dialogue.

For this achievement, choose the option to keep the tenebrium for yourself, unlocking You Keep Me Rockin. Reload and pick the other option to unlock Truth be Told