Plants and animals won’t behave normal as they are mutated due to the presence of a meteor. Plants and animals are not the only trouble but some big robots (of Dr.Croid) will make life difficult for Ratchet and company.
Although you enjoy the game alone but the basic theme behind is it’s cooperative interaction for a common goal. If players synchronize with each other, their attacks will be more effective e.g if all the players fire the Darkstar Fission Rifle at the same time, it will amplify the attack and hence cause more damage.
Although all the players need to coordinate with each other for overall progress, the one with more points will be rewarded better which can encourage players to compete in co-op mode of the game, making the game more engaging.
In All 4 one, each character will have a separate gadget which will also be upgraded over time. Ratchet for instance can use his Doppelbanger ability to create a decoy that draws enemy fire which after certain time will be upgraded to a powerful turret.
The game will support up to 4 player co-op either on the same screen, online or in any combination of online/same-screen players.The game is set to be released in 2011 but no date has been confirmed so far.