If you’re looking for the highlights, here’s the big new stuff in Gears of War 2, although there are far too many additions and changes in all aspects of the game to list here:
Meat Shields
Players can now pick up a downed foe and use the unfortunate chap as a bullet sponge! When you carry an enemy, you move at reduced speed, and you can use only pistol-class weapons. In exchange, your damage-soaking buddy provides a safe way to move across exposed areas with no cover.
The Submission multiplayer mode focuses heavily on this feature, as a computer-controlled target must be downed and then carried to a target area.
There is also an actual, non-flesh shield in the game. This functions similarly to carrying a body as a shield, but you can also plant the shield in the ground to use as a form of portable, stationary cover. You can also use it to perform a brutal execution… One important distinction is that a meat shield will degrade and be dropped once it takes a certain amount of damage, whereas a non-flesh shield does not degrade. Also, you can run with a non-flesh shield: you can’t run with a meat shield.
These features add mobile cover to Gears of War 2, so they impact all aspects of the game, both in the campaign and in multiplayer.
Vehicles
No more beat up Junker. This time around, you can pilot the mighty Centaur Tank during specific parts of the campaign. In addition, a few other special vehicles show up. Locust Reavers and even the awesome Brumak become living chariots for the Gears.
New Multiplayer Modes
Old modes have returned in a refined state, but Gears of War 2 has also added Submission, Wingman, and Horde, completely new forms of multiplayer.
Submission is similar to capture the flag…with a living flag. Wingman lets you and a buddy take on four other teams of two players each, and Horde is an awesome cooperative battle with four friends against the Locust.
Warzone is largely unchanged, while Execution, Annex, and Guardian have been modified. Check the multiplayer chapter for specifics.
Selectable Difficulty
Cooperative players can now choose their difficulty level individually! This is great if you’re a veteran but your partner is a newer player. Higher difficulty settings cause you to receive more damage and inflict less yourself, while lower difficulties act in reverse, greatly easing combat.
The War Journal
A new tool for organizing and cataloguing your exploits in Gears of War 2, the War Journal keeps track of your progress toward campaign and multiplayer Achievements, as well as giving you bits of back story about the world of Sera as you gather the 41 collectibles scattered throughout the campaign.
Check this guide’s COG Intel Archive chapter for a quick checklist of the collectibles, or use the main campaign walkthrough to track them all down—they’re marked on the maps and noted in the text.