Moonsigil Atlas is by far one of the most interesting and promising upcoming games I've played in a while, taking deck-building roguelikes in a fun direction.
Instead of a mana or energy system, you use physical space. Each card you have creates a certain shape to activate and place down, so it's all about making use of the space that's available to piece things together. You can manipulate the shapes of each individual card as you progress and upgrade too, and eventually get some really interesting overpowered combos going thanks to bonuses for overlap and adjacency.

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Since it's all about physical space, there's no real right way to play through or build up your deck. It gives you an interesting type of freedom to experiment during a run.
From the email sent to GamingOnLinux, here's some of what's included in the big demo upgrade for Steam Next Fest:
- Localization - The upcoming Next Fest Demo will be fully playable in Simplified Chinese, Japanese, Korean, and Russian (localization is currently work-in-progress and may have minor inaccuracies)
- Second Act - A preview of the game's entire second act will be available to all players in the Demo
- Forbidden Cards - New rare cards with powerful effects that can be acquired during a run
- Artifacts (Items) - Rare and powerful artifacts that grant the player passive abilities that can be acquired during a run
- A Ton of New Encounters - Shape Swapping (allows the player to swap the shape between two cards), Card Duplication, and more
- Even Better Visuals - We've added a ton of new visual effects, flair, and QOL visual features to the game
- Greatly Improved Tutorial - We've rebuilt the tutorial from the ground up to be interactive and spread out over the course of normal gameplay
- Additional "Character Mastery" Unlocks - There is more content to be unlocked over time while playing the Demo
- Steam Achievements - A selection of Steam achievements from the full game will be available in the demo.
I absolutely adore it. Definitely one you simply have to check out. The demo and full game have Native Linux support.
If you have any feedback after trying the updated Demo, I'd love to hear it.
- Daniel (one of the Moonsigil devs)