Rise of Nightmares

Grab a scissor-type weapon and start cutting away. You need 100 kills with a scissor-type weapon.

Easy if you load up Act 10 Scene 1. In the 2nd room with the 4 explodie creatures, there are hedge cutters. Just keep playing over and over until it unlocks.

Load up Act 5 Scene 2 (the part where you have to destroy the four towers).

Turn around after you start (so the portal is directly behind you), move toward the centre, then go to the first opening on your right. Ignore the zombie to the left and go up the stairs. On the left there should be some barrels. Kick them (the one at the back right is the one you need to break) and obtain the bone shears. Now turn around.

In front of you will be an explosive crate. Walk towards it and two zombies will drop down. Lure them toward the box and kick it to kill them (on normal, and if you need the achievement for killing enemies with explosive boxes, if not, just kill them with the shears).

Now go up to the tower, kill the three guys and destroy the tower. This is your checkpoint.

Go to the centre where all the enemies are dancing around, kill as many as you can before the shears "break" and then die. A good place to get killed is the opening to the right of the portal. If you are facing the portal. Go to the first opening on the right and a zombie with two creature arms will be there (on the left). It will run towards you, pounce on you and kill you quickly.

When you die, you will respawn near the explosive crate at the first tower you destroyed. Two zombies will drop down (the two zombies near the explosive crate from before) when you respawn, so step forward, turn around, and kill them. Before heading to the middle where the four zombies are dancing, Kill the zombie at the bottom of the stairs to the right, then head to the centre to kill the four dancing zombies.

Return to the area where the Zombie with the creature claws is. You can kill the zombie on the right before the zombie with the two creature claws kills you, then repeat.

You can get 7-9 kills before the shears "break" and you have to die and respawn near the first tower.

You need 100 kills for the achievement.