The decision over whether to enter the Planecaster in is more complicated than it seems. The party may be faced with this choice if they progress in the githyanki crèche questline, which eventually puts them face-to-face with the githyanki god-queen Vlaakith. Using Shadowheart's mysterious Astral Prism, which thus far has seemed to protect the party from Illithid influence, Vlaakith opens a portal to the Astral Plane, and demands that the party step inside and kill her prisoner. Unless the player has been following the lore very closely, it's difficult to understand just what this decision entails until they're already on the other side.
Entering the Planecaster seems like a pretty minor decision, but it may have shockingly severe consequences. Meanwhile, attacking the Astral Plane prisoner may seem a risky undertaking, but its own consequences are surprisingly minor. Remember, Tav's Dream Visitor has given them ample warning about the prospect of stepping through. Either way, though, these are the pros and cons of each option.
If the player decides not to enter the Planecaster at Vlaakith's urging, Lae'zel will disapprove. As a matter of fact, she dislikes this course of action so much that she'll immediately turn against the party and side with Vlaakith, her queen. The party will have to kill her to progress. This means the githyanki fighter will become completely unavailable to the party for the rest of the game. It should go without saying that this does more than hurt the chances of romancing Lae'zel in ; no matter how much progress the player has made with her, this decision cuts off the rest of her story.
However, once Lae'zel, Vlaakith, and the rest of the githyanki are dead, what remains of the party can
Read more on screenrant.com