To claim your Steam key (if you own 10YA on Desura), visit this URL: http://www.desura.com/collection
And find 10YA on the list. Click keys. Your 10YA Steam key should be there.
To activate it on Steam, open Steam and press 'ADD A GAME...' and then 'Activate A Product On Steam'.
Steam keys for Desura owners!
Build and release context
Recorded Steam release date:
Within one calendar day of this post (UTC). The listed date does not establish an exact launch time.