Would need a lot of control tweaking, both from Steam input and in game controls, but it looks like Mindustry might be less than a gig of storage. At least the free version you can get from either itch or github is.

Seems those versions are currently slightly less than 100mb for current non bleeding edge releases. I found the folder for my installed Steam version and it says it’s nearly 160mb, so there’s that. Didn’t realize it was such a small game, but it’s fun. Much better if you have a mouse and keyboard rather than just touch controls, coming from someone who started off playing it on mobile.

Only $9.99USD ( IDK what that would be in other currency ) on Steam to get steam supported things like workshop or seemless multiplayer, but if you are like me and only play single player campaign, the free versions are just as fine.

Sulfer is about 4GBs, it’s an excellent indie looter shooter with gun crafting and charm.

I’m going to go in a different, but important direction than everyone else: don’t.

SSD’s are constantly moving bits of data around to balance the amount of read/write each sector deals with, since that is what degrades the components.

The downside is that the swapping also counts as read/write cycles. Most of the time this is fine, because the SSD is doing relatively little data swapping compared to what it’s optimizing.

This goes away when your drive is more than 90% full. Then your drive become one of those missing tile puzzles, and it starts shuffling lots of data around constantly to get things in their optimal place. This leads to the swaps drastically increasing the read/write cycles and killing the drive early.

If you really need to have a bunch of games saved on your Steam Deck, you’re better off getting an SD card and using that for additional storage. While it’s slower to load, it’s not that much slower, and it’s not noticable for smaller games

Throw in a 1TB SD card and load it with ROMs. Install your emulators of choice.

Deep rock galactic is shockingly small

Im incredibly addicted to gambling rogue likes and a lot of them are quite small. Currently I’m really enjoying:

Raccoin Balatro Clover Pit Peglin Luck be a landlord

Celeste, the platformer, is one of my favorites, and it’s super small.

Haven’t seen anyone mention Slay the Spire yet. The original is under 600MB and the sequel (early-access) is 2GB. They’re both good! The first one is maybe a little easier, if you’ve never played them.

Abiotic factor

10gb, half life themed survival game. Extremely solid. The combat itself isn’t too crazy, I think you could pull it off on steamdeck

i’d grab a lot of old game roms for emulator. nes/snes/gba/mame stuff are tiny in filesize. there are tons of gems in nds/psp too. maybe gc/wii/3ds stuff too, but they’re significantly larger.

Outer Wilds is 8GB, and the best puzzle/mystery game I have ever played. The less you know about the game up front, the better.

Balatro is tiny, like 150 MB tiny. And endlessly playable. If you like poker and/or rogue likes it’s pound for pound one of the best deals out there both money and memory wise

I love Skald Against the black priory, and I’ve also started The wandering Village. Both well under that limit!

I have been playing Time Snatcher Handy recently, a roguelike centered around a time-stop mechanic, which only uses 44 MB. It is pretty good. Going through my steam library from the lowest up, here are the others i would recommend, stopping at one GB, because most of my games are under 20 GB and i tend to be relatively selective with what games i get so i consider most of them good also:

• TIS-100 (80 MB), programming puzzle game by Zachtronics
• Islanders (150 MB), minimalist city builder
• Enter the Gungeon (346 MB), bullet-hell roguelike
• Streets of Rogue (417 MB), roguelike which emphasizes having multiple possible approaches for how to get any given objective
• Opus Magnum (493 MB), another Zachtronics programming puzzle game
• Vault of the Void (554 MB), roguelike deckbuilder (one of my most played games, especially recommended)
• Backpack Hero (616 MB), roguelike focused on maximizing adjacency bonuses on your inventory grid
• Urbek City Builder (685 MB), city builder (obviously)
• Slipways (735 MB), a game about optimizing trade routes between planets
• Cassette Beasts (1 GB), similar to Pokemon, with the main differences being that you turn into the monsters instead of summoning them, type advantage/disadvantage giving unique status effects rather than just changing damage and battles generally being 2v2 instead of 1v1

Minecraft (Java Edition, the standard).

About 0,3 GB, and needs no introduction. Endless box of fun in a tiny cross-platform package.