They say there are five stages of grief...

Who denies it:

Error

Whos angry

Basically, the enitre gang

Whos bargaining about it:

Dust

Who falls into depression?:

Killer

Who refuses to accept he's dead:

Cross+X!Chara (he was like a dad to both of them)

Well we're going to add one more...

Who would want revenge?:

Dream, Killer, Dust, Cross, X!Chara, Horror, And Error