How do u get ectoplasm?

[Kloopa]

I saw videos on how to get ectoplasm so now I know but u need to go to lava level in ur dungeon but my dungeon doesn't go near lava level! So I don't think I have a way to it? Or do I? Please tell me if I can get it and how or I can't get it and why not.

[bad]

You don't need to be near lava level, that is ♥♥♥♥♥♥♥♥. You need to be in Hardmode and kill a Hardmode boss. After that, a pink bulb will spawn in the Underground Jungle. Destroy it to summon the Hardmode boss Plantera. After she is defeated, your dungeon will contain HM dungeon enemies. Kill those. They have a small chance to spawn a little Wisp when they die. Kill that thing and it drops 1-3 ectoplasm.

[Kloopa]

I knew plantera would come back and haunt one of these days! Now I have to make a discussion asking how to kill plantera!