assuming you mean the helm, since wither's a spell, yeah.
look at the grey text under the gem name to see which tags it has and which affixes apply to it
since wither stacks up to 15 though, and asenath's has a built-in 0.3 second cooldown, you wouldn't have max stacks until a minimum of 4.5 seconds while attacking the same target.
would be best to put wither on a multiple totems/spell totems/faster casting 4link and use asenath's for despair instead imo. if you're looking to put this 4link inside the helm to get up to 15 stacks faster, then that's smart too.
This post was edited by Wretch on May 15 2021 09:54am