The Steam Deck is just a Linux PC, you can absolutely mod games on it!

I’m playing modded Slay the Spire a lot on mine.

I guess the level of scariness is subjective, at least from what I’ve read not everyone seems to agree that it’s very mild :P But I’ll definitely play it eventually, the base game is one of the best games I’ve ever played.

My backlog and my library are huge so I’ll choose a few (in no particular order):

• Baldur’s Gate 3
• Cosmic Wheel Sisterhood
• Inscryption
• Hades
• Hollow Knight
• Outer Wilds DLC (I’ve been putting it off because it’s supposedly scary)
• Stray
• Little Kitty, Big City
• Monster Train
• Moonstone Island