Aliens: Colonial Marines

Play "The Raven" mission and proceed until reaching the room containing Boilers. Sneak past them and use the sewage pump switch that will start a distraction and kill the Boilers. Continue to the generator until reaching a four-way intersection. Go to the right, toward the dead end. Get close to the barrels to find a Newt's doll's head and interact with it to earn the trophy.

Destroy the third AA gun in mission 10, the continue through the rocky exterior to a destroyed building. You will find ammunition to the right of the entrance, and a destroyed floor past that point. Stop just before exiting this building. You will see a sheer drop past the exit that leads to a large open area. From this position at the exit, look to the far right with a scoped weapon to see aliens spawning above the spotlight. They will then run across the roof before jumping down. Remain inside the building and do not drop down into the open area and those aliens will always respawn. Kill them from the building until you need more ammunition. Then, reload the last checkpoint and repeat the process.

When fighting the alien with the powerloader, be patient. Use the controls as if you were boxing by jabbing, moving away, then jabbing again. Do not rush the fight.

Proceed through the "For Bella" mission until you get the "Find a way into the Weyland-Yutani Facility to save Bella" objective. Follow the stairs to a door, and exit the interior to enter a rocky exterior area with lava flowing down a cliff to your right. Run partway up the path ahead and look to the right across the chasm with a scoped weapon to find a box of donuts. Shoot them and they will disappear. Then, look to where your teammates are waiting to see a giant donut appear uphill. It will roll down, launch off the cliff, and explode in the lava.

Proceed through the "For Bella" mission until after you drop down through some debris. Look inside the locker next to the sentry gun to find three spheres that resemble like the special stage symbols from Sonic 3 And Knuckles.