While exploring the many worlds of Psychonauts 2 you'll occasionally come across narrow slots on doors. You can actually get through these with the right powers, but you'll need to play through a fair bit of the game first. Here's how to unlock the Projection skill.
Psychonauts 2: How to Get Through Narrow Slot Doors
To get through locked narrow slot doors in Psychonauts 2 you will need to use the Projection power. This skill conjures a 2D version of yourself that you can use to squeeze through the slot. You'll learn this from Cassie O'Pea, later on in the game. This section is a main story mission and occurs after you completed the 3 main missions involved with the Bowling Alley, Psychoisolation and Mailroom areas of HQ. it's a fair way into the game, so just keep playing and you will be guaranteed to receive the Projection ability.
Once you have the Projection ability just equip it and interact with the narrow slot. You'll crawl through, allowing you to reach new areas and collectibles. You may want to go back to areas you might have missed by replaying levels.
There's a Scavenger Hunt to be completed while playing through Psychonauts 2. Visit our Walkthrough for tips on finding all 16 items.
What's Behind the Locked Narrow Slot Doors?
You'll mostly find collectibles behind these locked doors. There are even some items from the Scavenger Hunt behind them, so make sure to unlock and check each one of them. you will need to do so to get 100% completion.
That's all you need to know about using narrow slot doors in Psychonauts 2. For more on the game be sure to check out our guide on reaching Dark Thoughts grapple points.