Hostile Takeover Achievement
Complete the Royal Deadfire Company faction questline.
Royal Deadfire Company quests are given by Hazanui Karū and Atsura (both located in the Imperial Command). Just follow the questline – it is all rather straightforward. The “point of no return” here is obvious as both Hazanui Karū and your journal will point it out. It comes with a quest “The Final Maneuver” – if you do that one, you will forfeit every other alliance and bind yourself to RDC. So, save before agreeing to commit to Hazanui Karū if you want to pursue other faction quests first.