If a shapeshifter becomes a copy of a god, it has the creature type unless otherwise started
Where Sabrina forces your opponent to switch out their active card, Cyrus allows you some control over the choice: You can swap in any Pokmon thats not at full HP, effectively nullifying attempts your opponent makes at retreating a damaged card
Given how good the archetype is in the format, Sephiroth was an easy top pick for that reason
Decks that create Thopter tokens or other artifact creatures can use this to buff their armies and as a source of card draw
Since [Zendikar Rising]s a land set, one option is always a land, but it lets the other side be an effect that might be too narrow to play by itself. That meant the Magic team could create more cards that both fit Zendikars theme, but also created chances for niche abilities
This deck has been play tested and is remarkably strong, not to mention a ton of fun to play