Get games like Pathfinder: Wrath of the Righteous, Baldur’s Gate Enhanced Edition, and a pre-order of MythForce. Pay what you want & support Active Minds!
I already own all of these titles on multiple platforms, but if you're missing any of these classics, now's a good time to build out your Steam library for just a couple bucks per game.
It's a good deal. I've seen various packages of the old Infinity Engine games offered for $9.99 on GoG, and that sort of thing, so depending on what games you already have, you may get lucky if you wait for a similar deal at another time.
But if you need several of these games, and you think you'll play them, it's a solid offer. Pathfinder: Wrath of the Righteous (technically a "D20 open system" game, not D&D) and Dragonspear are new-ish and arguably worth a few bucks on their own.