pithing needle if i have a pithing needle in play with naming necrotic sliver would the other slivers in play be able to use the ability or would it cancel the whole thing.
Other non-Necrotic slivers can still use the ability. Pithing Needle does not stop Necrotic Sliver from granting each other sliver that ability. Only cards named Necrotic Sliver will be prevented from using that ability.
Pithing Needle will only prevent Necrotic Sliver from using its activated abilities, it will not prevent other Slivers from using the ability given to them by Necrotic Sliver.
needle.