Steam

Hades is a steal at 5$, if you're into more casual gameplay vampire survivors is also a steal at 3.50 (includes all the dlc), if you want something in between brotato has been a wonderful purchase for me. If you want more of the frantic play style, but shorter sessions and less RPG decision making elements, 1 finger death punch is only a buck.

All of the source games are on sale, I recommend portal> portal 2 /half life 2 > left 4 dead 1&2

Slay the spire for < 2$ is an absolute steal, if you think you might like deck builders that's one of the o.g's. another most excellent deck builder, monster train, is also less than 2$, I cannot recommend them both highly enough.

The room is an excellent puzzle game, especially for 75 cents, not personally sure about it's sequels but I've heard they're equally good.

Don't starve for 2.50 is amazing, but if you're at all multiplayer inclined, get 'don't starve together' (I believe it comes with a second copy you can give to anyone)

Hexcells, hexcells 2, and lyne are great if you like puzzle games (everyday genius square logic is also great, but not on sale and no longer supported by devs) delete is also good, and on sale, but it's much more once over it's done game (like the room)

Doom (2016?) Is a great first person shooter at 4$, and fallout new Vegas is a great first person RPG at the same price.

FtL at 2.50 is amazing, and after you've sunk a hundred hours into it, download the 'across the multiverse' fan made expansion, and sink another thousand hours into the game.

And if you're considering Diablo 4, I plead with you to give path of exile a fair shake first, it's free to play, only cosmetic micro transactions, and so much more fleshed out of experience.

I stand by each of the above games, if you give any of them a fair shot and walk away considering it an actual bad game, hit me up, let me know what made it bad, and I'll toss you a game key (of my choosing) of equal or greater value (than the sale price of the game you thought was bad)

Edit, not sure where the hell I got those prices from, I think it may have been showing me "complete the bundle"prices on games I already owned that had bundles with everything else I also owned? I'll go through and change my reviews based on the prices I find, it'll definitely change a couple of my "absolutely must have at this price"