Won a questionable game earlier today, what do I do?

Dont mark as received ?

It's not allowed, only Steam keys are allowed here.If key doesn't works on Steam, wait 7 days and mark is at "Not Received".

He probably gave you an uPlay key for the game.Contact the gifter,if he doesn't give you a steam copy of the game mark the giveaway as not received after 7 days have passed.

Sounds like its a uplay key.

Only Steam redeemable games can be given away. The key may be legit, but it sounds very suspicious. Either way, you can't mark the game as received as he was supposed to be giving away the Steam redeemable copy of Assassin's Creed 3.

I actually have had a similar issue with someone who won mine, and I jumped the gun on support apparently. He marked it as received and I haven't been able to contact him to send it properly.

Report it to mods, it's really ilegal here, the gifter can only gift Steam keys or gifts.

Once 7 days have expired, you can mark it as "not received". For now, I think if you click on "received" you can toggle it so it reverts to "waiting".

As others have said though, this should be reported to Support by raising a ticket. What he has given you is bullshit. Dodgy Russian websites and torrents have no place in the process. He either needs to give you a Steam gift, or a working Steam key. There are no other options.

Jesus..."only steam keys can be given away"...so what?! Copy it into uplay and have fun. Uplay is necessary either way.

Uplay key