During the season, you will play across a number of 'unknown' wrestlers which are mostly from the WCW, which you can unlock. They are not actual wrestlers, but moves and taunts that are unlocked and can be used in creation mode.
The following are from the WWF:

Big Show (Show Stopper)
Ken Shamrock (Shamrock Ankelock)
Bob Buckland (Chicken Wing Cross Face)
Jerry "The King" Lawler (Piledriver)
Sgt. Slaughter (Cobra Clutch)