Rocketbirds 2: Evolution is a gleeful 2-D platformer that pairs a gritty, murky art style with a deadpan sense of humour.

Gameplay is tough, but rewarding, and fans of the original will enjoy the new co-op Rescue Mode, in which up to four players can join in the fun.

The sequel to 2011's Rocketbirds: Hardboiled Chicken (both developed by Ratloop Asia), this game picks up where the original left off. Players still control Hardboiled Chicken, a chicken super soldier that looks oddly like Hulk Hogan, with a wattle moustache and bandana.

The enemy is still Putzki, a despot penguin that gives speeches from looming Big Brother-esque screens, and who squawks petulantly, "The chicken also called me a dork!"

Players have to fight their way through the penguin fortress, and make mincemeat of all the clueless poultry along the way.

The platformer is largely free-roaming, but from time to time you will be locked into single- screen fights as a door shuts behind you. These setups tend to be the more difficult segments, as tougher enemies turn up, and there is little room to retreat or outmanoeuvre melee enemies.

It takes a lot of madcap running and shooting (and probably quite a few tries) to get it right, but, once you do, it is satisfying.

For me, the real fun was in the co-op Rescue Mode, a new addition. In it, up to four players can play either online or offline, and have to battle through levels to rescue stricken chickens.

Players cannot just run alongside each other, but they can jump on top of each other to form a majestic stack of chickens.

This means that while the player at the bottom concentrates on moving, everyone else can just fire away without having to worry about manoeuvring.

There are also other ways that multiple players can take down enemies, such as one kicking the enemy to stun them, while the other shoots.

Lisabel Ting

•Verdict: A tough yet satisfying 2-D platformer with a very enjoyable multi-player mode.