Any effects that increase or decrease the cost to cast it will also be taken into account
You can also use it to generate additional storm count and even mana by bouncing your own stuff and taking advantage of making copies, lands be damned
See rule 702.86, Annihilator. 702.86a: Annihilator is a triggered ability
Book Devourer Borrowed Knowledge Brand Break Asunder Breakthrough Byway Barterer Canyon Crab Careful Study Carnage Interpreter Case of the Crimson Pulse Catalog Cephalid Sage Ceta Sanctuary Chains of Mephistopheles Chakra Meditation Chandra, Flame's Catalyst Chandra, Flamecaller Change of Fortune Choking Tethers Claws of Wirewood Clear Clive, Ifrit's Dominant Cloud of Faeries Complicate Compulsion Conqueror's Foothold Contract from Below Control of the Court Cool but Rude Coralhelm Chronicler Cram Session Customs Depot Dangerous Wager Darkwatch Elves Death Pulse Decaying Time Loop Dirge of Dread Disciple of Grace Disciple of Law Disciple of Malice Divide by Zero
If the person youre trying to buy for always buys their own cards, and theyve already got everything on this list, then getting them a gift card for an online TCG store such as Magic Madhouse in the UK or TCGplayer over in the US - or, ideally, their friendly local game store, is an excellent way to make sure theyll be happy, but still shows youve put some thought into things
Orcish Oriflamme was printed with the wrong casting cost in Alpha
