Two things to note: Not EVERYTHING before a semi-colon is a cost (though they're never effects, but just the same, declaring card names, etc. isn't a cost), just stuff you do upon activation. And second, this wording scheme only applies to activation costs. MAINTENANCE costs don't use a semi-colon. (Spiritual Energy Settle Machine won't trigger Dark Worlds for example.)
I wonder if this card works with Goblin Circus to recover some banished monsters that are facedown?
Archfiends already have Escape which is a trap card and does not have a cost. The trap version is better because it can activate during battle phase or during your opponents turn. This new card is more universal however, since it can revive any banished monster not only dark ones. It will mainly benefit other decks, Archfiends not so much, but still a good alternative.