Gears of War 2 Reavers tip

Avoid the Duel
Chainsaw duels are fun, and winning them brings with it a special kind of gory satisfaction, but any time you engage in a duel you also run the risk of losing. With the new backstab chainsaw attack, you can take this possibility out of the equation. Focus more on sneaking up behind enemies rather than charging them.
Reaver Belly
Reavers were seen but largely not heard from in the original Gears, but in Gears of War 2 these frightful enemies consistently join the fray. Luckily, they can be handily defeated if you exploit their weakness.
Rather than duke it out with a Reaver at long range, sprint under them where neither their melee nor ranged attacks can reach you. Then, use blind-fire to rip into their belly with your weapon of choice. You can aim if you want, but there’s no need to, and doing so will just make it more difficult to stay under the Reaver as it moves about.
Try carrying two weapons with different strengths. For example, if you pick up the flamethrower, use it to replace your shotgun as both work best at close range. If you’re already carrying a torque bow, there’s really no need to grab the sniper rifle as well. Combat in Gears of War 2 is very fluid, so make sure you’ve got the tools you need to engage at both close and long range.
Pistol Time
It’s not uncommon in Gears of War 2, especially on Insane difficulty, to find yourself having to ration bullets. In order to avoid ammo shortages, try taking down easier enemies like wretches, tickers, and low-level grubs with the rarely used pistol. Keep your more powerful weapons in reserve for the tougher creatures.