I'm building a [mtg:Jon Irenicus, Shattered One] deck and wanted to know how his ability to give a creature "this creature can't be sacrificed" would work with something like [mtg:Blood Pet] or even [mtg:Mausoleum Wanderer]? Would I just be unable to use the ability? Would I make infinite black or counter spells for free?

I also wanted to confirm if he can actually end the game in a draw with some like [mtg:Merchant Ship] or [mtg:Pirate Ship] if anyone has an answer? I believe it would because of a mandatory loop but want to be sure.