Although Valve doesn't provide verification for game demos at this time, Isle of Reveries is being developed and tested with Steam Deck in mind, so the demo is fully compatible by default. No need to fiddle with Proton versions or gamepad configurations!
The Isle of Reveries Demo has received a couple of reviews from players that primarily played on Steam Deck:
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"I'm a big fan of both traditional 2-D top-down Zelda and the GBC pixel art aesthetic, so IoR is right up my street. Clearly a lot of love and attention has gone into crafting this demo. Looking forward to the full game." -- Steam reviewer
"i am a bird" -- Steam reviewer
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