You can either nuke it from orbit (it's the safest way) or.... dig lots of tunnels and make heavy use of the clentaminator. But I will warn you this method is painfully slow and if you miss -1- block, a few game days later and it will all be corrupt again. Or Tedit. Batch convert corruption to normal, but then all corruption would be gone.
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Xylia
Xylia
That was a movie reference, lol. But in all seriousness, you could use bombs and dynamite to blow it out but then you'd have a giant hole in the world or you could replace it with something as you go.
T
Terrariaplayer123_
I got the reference 
It was just a vague explanation. Thank you! Not sure which to do though, as a huge hole in my world doesn't sound enticing.
It was just a vague explanation. Thank you! Not sure which to do though, as a huge hole in my world doesn't sound enticing.
Xylia
*nods* The clentaminator is probably the best bet, just dig a series of tunnels that are roughly the max firing range of the thing apart and go from there. It will take a good long time, though.
T
Terrariaplayer123_
Ugh, hoped it wouldn't come to that. Oh well, thank you
Xylia
I would also dig some corruption barrier tunnels.... tunnels that are 3-4 blocks wide every so far, so that if you do leave a small bit of corruption somewhere, it can't go far.
ThePally
I hope you have it contained already?
Xylia
If he doesn't, that would indeed be the first order of business is to hurry up and dig some containment tunnels...
Xylia
Also, if no complex built structures exist, it might be worth it to start a new world and build a base, dig containment tunnels first, kill the bosses up to where you are (this is very quick and easy with a hardmode character) and there. problem solved.