The Grudge Match is a long running series on IGN and over the years the most heated response has come from the old battle between Microsoft and Sony. While Nintendo reaps the rewards of mass market appeal, these two juggernauts are firmly entrenched in the battle for the hearts and minds of hardcore gamers. That's why they've kicked of a series of Grudge Matches that pit the two consoles against each other in every aspect of gaming. Today they start with everyone's favorite genre: the first-person shooter.

Both Halo 3 and Killzone 2 are more than just pieces of software. These brands represent everything Microsoft and Sony tout as the reason for owning their gaming consoles. For Microsoft, Halo is the flagship that roped millions of gamers into becoming Xbox Live Gold members. Its online co-op modes and massively popular multiplayer keep the title atop of the Xbox Live popularity charts over a year after its release and alongside huge brands like Call of Duty and Gears of War.

Killzone 2 is no slouch when it comes to multiplayer but its hook is that it just might be the prettiest game you've ever laid eyes on. Ever since the infamous CG trailer debut at Sony's E3 press conference, gamers have been obsessed with this game's visual detail and its ability to do something that probably isn't possible on rival hardware.