"altiFC" is a German professional high stakes poker player.
When playing on PokerStars, altiFC mainly focuses on No Limit Hold 'em and he is considered one of Germany's best on the format, particularly in the heads of format of the game.
Regarding his preferred screen name, altiFC, I could be dead wrong off course, but if I had to guess under gunpoint. I would put what's left of my life in the middle, and go with that it's short for, Altrincham F.C. a football club from the Greater Manchester in England. A club not quite up there with bigger and better known teams from Manchester. Still Altrincham F.C. is a club with a proud history and has beaten several teams in the FA Cup through the years, that's been out of their league, sort to speak.