Mountaincore has been built and tested to be fully Steam Deck compatible. The game ships with a default controller configuration - the default "Keyboard and Mouse" controller config. The controller settings are as follows:

• Left Stick - Pans the camera
• Right Stick - Moves the mouse cursor
• Right touch pad - Also moves the mouse cursor
• L1 & R1 - Zoom the camera in and out
• R2 - Simulates a Left Click i.e. a positive confirmation click
• L2 - Simulates a Right Click i.e. cancelling the current selection
• A - Pause or Unpause the game
• X - Rotate furniture that is being placed

The on-screen keyboard is displayed automatically when text needs to be entered, and the tutorial walks you through the Steam Deck controls rather than default desktop controls when the game is running on the Steam Deck.

Following all of the above, we believe the game is fully compatible with the Steam Deck and should receive a "Verified" badge, but we have to wait for Valve's official compatibility review first.

Here's a video from the YouTube channel "The Steam Decker" showing it in action: