The Seal the Deal DLC for the very good "collectathon" platformer A Hat in Time went live on Steam today, and if you want it then I'd strongly urge you to grab it right away—because right now, and until roughly 2 pm Eastern on September 14, it is free for the taking.

Seal the Deal adds a full new chapter to the game set aboard an Arctic cruise ship, and an "incredibly difficult" new mode called Death Wish. There's also six new Time Rifts, new outfits, flairs, dyes, and camera filters, and local split-screen co-op support. It will normally go for $5, but developer Gears for Breakfast announced in August (and confirmed today) it will be completely free for the first 24 hours of release.

A specific end-time for the freebie isn't listed anywhere that I've looked, but the developers tweeted that it was live at 2:04 pm Eastern today, so I'm counting down from there. Basically, if you want it, and it's not September 15 (or later) yet, get over to Steam or GOG to grab it. The base game is also on sale on Steam for 40 percent off—that's $18/£14/€17—until September 17.