Cactus Game Design Message Boards

Yep. The same way you can use Gates of Hell on your opponent's deck...

The Gates of Hell
Type: Fortress • Brigade: None • Ability: None • Class: None • Special Ability: At any time, you may discard the bottom card of deck. If it is an orange demon or a Lost Soul, place it in your territory instead. You may discard this card to add your demon to the battle. • Attributes: Plays to set-aside area • Identifiers: None • Verse: Matthew 16:18 • Availability: Thesaurus ex Preteritus booster packs ()

 

But seriously, it seems to be a necessary rule (if unwritten, I'm not sure) that when it doesn't specify whose deck, it means yours.

So I can target my opponent's deck and take their evil card and rearrange their deck?

No. Apparently you misunderstood my post, which was a bit tongue-in-cheek I suppose.

You cannot target your opponent's deck with a card that just says "deck" without specifying whose deck. Otherwise, if you could, I could discard your whole deck as soon as I drew Gates of Hell, put your Lost Souls and Orange Demons in my territory, and then rescue the shuffler with SoG/NJ to give you all of your souls back. That would not be a fun game.