Dead Space 2

In Chapter 7, find the mainframe room where ANTI is located. The circuit room that is to the left (when ANTI's hologram emitters are behind Isaac) has breakers that also turn blue in addition to green or red. Insert the four breakers in that circuit room to change them to blue. Follow the access tunnel to reach Peng's Treasure.

In Chapter 7, immediately after Isaac starts the elevator to go to the Solar Array area, a group of Tripods will appear. Use the Detonator to shoot them. Hitting a Tripod with the Detonator anywhere on the body will usually knock it off. Use Stasis to hold a Tripod in place when more than one of them appears. Knock off all Tripods in this sequence to unlock the achievement.

After the train scene in Chapter 3, you will enter some shopping areas. The second area has a fat blue statue. Shoot the head and arms off the statue to earn the achievement.

If you are finding the Stalkers troublesome, the best weapon to use against them is the Line Gun. Try to find an area to back yourself into then simply wait and aim. They will eventually pop out and run at you. The Line Gun will easily dispose of them.

Note: This only affects the current level. Exit out to the main menu, then return to the level. You can use the the weapon loadout screen to change weapons. You will resume with the default ammunition for that weapon. Note: You can only select the left special weapon; the other two special weapons are deleted from your inventory.