No, only if you want to play Duels of the Planeswalkers.
yes you have to have steam.
Steam is not a necessity for Assassins Creed 3. if you are speaking of online play then you will need to buy an online UPlay pass if one did not come with your game. Hope this helps!
Yes, if you are on a PC.
You need half life if your want counter strike and Steam if you want to play online you can also buy it from Steam..
Yes the newest war-games need steam because to play online they must have a network where u can chat and play. PS3 have PS network, Xbox have xbox live but we have steam!
No, you cannot play Day of Defeat: Source without Steam. The game is tied to the Steam platform, which is required for installation, updates, and online multiplayer. Players need a valid Steam account to access and play the game.
no it doesn't need steam
Well you can go online but need steam to find servers and you can play as singel player with bots just google it
Yes, you can.
If You want to play on steam servers than yes, but if you want a non-steam version(You can only play Non-Steam Servers), you can download off megaupload, rapidshare, or torrents. Just google non-steam condition zero and the online patch, download them, and you got it!
MW2 game which inturn installs "steam" onto your PC . That's all you need MW2 runs from steam.
You can't