This is my list about the games I consider the best games for 4-players local multiplayer in the PS3, I hope you'll like it !
Remember that my opinion may be different than your.
My Top Playlist : [ Ссылка ]

5. Super Sonic Acrobarit Rocket Powered Battle Cars
What a long title we have here, huh ?
This game is a Soccer+Cars made in Unreal Engine, it's really funny if you have 3 friends that likes this kind of game, the cars almost fly in all the stadiums and you can even destroy enemies or hit your team mate to do a gol with assist. Graphics are pretty good and it supports even the HD of 1080i, 1080p, the game is always 60fps, no slowdowns even in 4 player split screen mode !
Is available only for PlayStation Network and it supports online play with local players.

4. CastleCrashers
Awesome multiplayer hack 'n slash (in the style of Golden Axe) 4-players game with RPG elements. This game comes from NewGrounds (the same developers of the PS2 game Alien Hominid) and it has the same art style of the design and for thhe graphics !
Full of power-ups, unlockables and combos, this game is an awesome adventure to play with 3 friends in a bizzarre world full of crazy stuff that will gives you more than 10 hours of fun and entertaiment. The soundtrack is taken from artist of the Newgrounds and all of them are awesome, too bad we can't hear "Jumper" more than 1 time =(.
Is available only for PlayStation Network and it supports online play with local players.

3. Modnation Racers
Little Big Planet fused with Crash Team Racing, for me, it's a childhood dream that becomes reality !
Still not better than the perfect Crash Team Racing (best racing game ever in my opinion), this game is still awesome and the most of the fun goes in download user created stuff... and trust me when I say you'll find EVERYTHING if you're searching for a character or a track ! You can use your own music in this game... so, if you're playing a CTR or Jak X cloned track, you can use the right music ! This game supports local 4-players multiplayer and online with 2 players in the same console, which is really cool, who does not like kick online asses with a friend ?
You can find this game in a PS3 Blu Ray Disc and downloadable from the PlayStation Network !

2. PlayStation All-Stars Battle Royale
This is probably my favorite PlayStation 3 game after Uncharted, Ratchet & Clank future series and InFamous 2, I play it almost every day with my friends and it has a really competitive 4-players gameplay ! The roster of characters in this game is something awesome, we have finally got the chance to see Sir Daniel Fortesque, Jak, Spike and Parappa again ! The balancing of this game is really good (except for Kratos but hey, they'll patch him soon) and the stages are something unique... any stage of the game has 2 PlayStation worlds that will collide ! This game, if you have good friends, will give you hours and hours of entertaiment so I suggest it to you... also, if you're nostalgic with PlayStation characters, this is something like a childhood dream that comes true, I even know 5 guys that bought a PS3 only to be able to play this game !.
It supports online multiplayer with 2-3 players in the same console, so unlimited multiplayer ways to play it ! This game is available on PlayStation 3 Blu-Ray disc and in the PlayStation Store (for only 15$ / 15€, so I strongly suggest to take it).

And the winner is:

1. LittleBigPlanet 2
This game is... EVERYTHING ! Local (and even online) multiplayer in this game is god !
As I said for the Modnation Racers review, the most of fun in this game goes around the user created content... and some of these may be considered actually completely new games and, if you see them, you may even don't figure out that is LBP2... just let you understand how the level creation in this game is powerful !
This game gives to the players an almost infinte number of awesome co-op and versus levels to play together... to me, it's the ultimate 4-players game ever !
I strongly suggest the "Best Mortal Kombat Ever", the Minigolf levels and the Billiard levels, they're awesome ! Also, Paint gun levels are quite fun... It turns the game into a Metal Slug type of game ! And not forget about party minigames... am I suggesting too many levels ?
This game is available on PlayStation 3 Blu-Ray disc and in the PlayStation Store !

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