Rejoin the Fight may cost six mana, but the effect is well worth the cost
Vivi not only grows bigger and hits the opponent the more spells you play, it then turns that into mana, which you can use to cast even more spells
Each Item is played to the board by their ink cost and then allows the player to use the abilities stated on the card
Similarly, The Warring Triad has a stipulation on whether or not it's a creature on the battlefield
That part is going to require some considered deck building and a bit of luck
The lack of red mana in this theoretical deck puts a limit on the number of Final Fantasy Wizards you can consider, but theres still Venat, Heart of Hydaelyn, who lets you draw a card every time you cast a Legendary card