Your top 3 free FPS games

first person or frames per?

Hawken - favorite Mech vs Mech FPS
MechWarrior - probably great but wasn't motivated to play it
TOXIKK - provides since recently a F2P Version should be good ...
Titanfall - not free, exploding trash cans as Mechs + too much COD garbage - still OK

Black Mesa? I don't mean current version in Steam shop.

Wolfenstein: Enemy Territory i havent played it for longlong time but it is my top free FPS.

Only free or f2p also okey?
Best f2p FPS TF2 and third QL.

Warframe, there are no others!

Lead and gold: Gangs of the wild west. Very nice reminds me of a mix between tf2 and dead redemption. You can get it on SG somewhere.