How do you kill what's already dead?

[Mighty Lighty]

Yell "LOOK AT THAT DIRTY HIPPY" and let Saxton hale do the rest
(you may need to flee the planet once he realises he's been tricked)

 

[dkyros]

Spirit bomb or sending into a star comes to mind

 

[Knusper]

Get 2 things that are good at killing and then combine them together. You just have to kill them harder.

For example: Molotov Cocktail? Machine gun? Molotov cocktail machine gun

 

[HyperionToASatyr]

Does it bleed?

If so, then you can kill it.

 

[Hunter15]

get chuck Norris or Reb Brown to fight it it will rather eat its own head and implode on itself then fight those guys

 

[Simriel]

That is not dead which can eternal lie.
And with strange aeons even death may die.

 

[NeoShinGundam]

Eject it into the Sun!

 

[Qmonster]

The double tap.

 

[Kakashi on crack]

You use your mind.

A zombie is a physical creature that can refer to almost anything from a skeleton to a vampire. If it isn't a zombie, then it is a wraith or ghost of some sort, and as such they use energy. The human mind has unlimited stores of energy compared to any apparition, and can be used to harm/kill them.

 

[razor343]

Shoot from the hip and aim for the head. - Creature Feature.

 

[Byere]

Spirit bomb or sending into a star comes to mind

Naw, you just summon the Makyo Star and trap it in the Dead Zone

 

[flagship]

Bring it back to life then kill it with fire?

 

[Dark_Fuzion14]

Rip its head off and shit down its throat!

 

[2fish]

Acid or fire, maybe both? If you break it down then it is not a problem.

OR

If you want to be technical:
Bring it back to life then blow its fucking head off

 

[cthulhumythos]

Not zombies.

bring it back to life and then kill it.