correct me if i am wrong but if sliver overlord is in play and crystalline sliver is also in play, you can't use overlords power to search your deck for a sliver card because you are targetting a sliver.

However can i use eladamris call to search my deck for a sliver if crystaline sliver is in play

http://sales.starcitygames.com/cards...damri%27s+Call