Unable to buy final power upgrade (Psychonauts 2)

Ok, well, first of all: woah, congratulations. You really did everything? Thanks for playing! The manual screens in the game should verify whether you're missing any collectibles in any of the areas. If, after looking at that, you're still certain that you've hit a wall, then unfortunately you might have hit a rare issue where you can complete everything and end up with fewer intern credits than you need to unlock the last power.

Unfortunately so far we haven't been able to reproduce this issue, so we're not sure what causes it. However, if you're on Windows/Mac/Linux and not playing on Game Pass what we may be able to do is provide you with a workaround. If that's you, get in touch with us at support@doublefine.com and we'll get back to you as soon as we can.

If you're on Game Pass or playing the console version then I'm afraid we don't currently have a workaround for this. We know that's not ideal because you probably really wanted that achievement/trophy for finishing everything but unfortunately we won't be able to assist at the moment.