Brain of Cthulhu
Yes, but you won't spend so much time on the vortex tower, you have to beat it only once per entire game. And only 1 enemy at this tower gives you this debuff.See, no matter how common Armored Skeletons are, you can avoid the debuff pretty easily by not touching them. Same with Pixies and Mummies.
The reason why I mentioned Webbed/Blackout/Distorted in particular is because even though they are rare, they are deadly when you encounter them, and the enemies that inflict those debuffs on you can do so without touching you.
You can’t beat the game without destroying the Vortex Pillar, and the Ankh does nothing against Distorted. You can’t beat the game without defeating the Twins, and the Ankh does nothing against Cursed Inferno. No matter how you look at it, the Ankh is just not as useful as advertised; it fails to save you from debuff-related hazards at critical times.
Basically, if you die because of a debuff, odds are that it wasn’t a debuff that the Ankh Shield would have saved you from.
And cursed inferno is actually a debuff, that is difficult to get even get in the spazmatizm fight. You can avoid his flame attack easly.
And you don't have to go to the spider caves to beat the game, it actually just gives you some summoner items and armor and due how scary wall creepers/black recluses look, i avoid entering this biome. Anyways again, before hardmode there's no such a thing as black recluse and wall creepers aren't that annoying, so you can remove it in pre-hardmode and when you entered hardmode, you don't need to worry about these debuffs.
And yes, avoiding spider caves is easly, spider caves never spawn in underground jungle. But in underground jungle you'll get annoyed by the "Poisoned" debuff. And what helps you against it? Right, good ol' ankh shield.