The fact that the second card is so loosely restricted, and Force is so universal (and technically hard-castable) makes it playable in any fair blue deck, and so gives a large portion of the format the necessary panic button to discourage super-aggressive combo
Sets Inventory Decks Wishlist Trade
Legendary Creature - Cleric Elf Anthem (CTRL to add secondary) Counters Ezuri, Claw of Progress Whenever a creature you control with power 2 or less enters, you get an experience counter
Fact or Fiction
It's quite mathy, but he goes into a great deal of detail and explains his rationale, while not ignoring the realities of the game (there are one-mana Cycling cards, cards that fetch lands, cards that tap to add mana which aren't lands, and more.)
Its essentially most of a Champions Helm but for a good deal less mana, especially if your creature is three or more colors