Abbot of Keral Keep starts to approach 100% of an extra card as the game goes on, though there is always some amount of limiting of options because of the timing
Its an inherently aggressive gameplan, both because youre cashing in your resources to maximize short-term damage, and because flooding the board makes you incredibly vulnerable to sweepers and other late-game effects
Digital product: nothing is shipped
In most use cases, thanks to the treasures you should be getting back from this, youre simplifying the board considerably for between 0-3 mana on average, except that mana goes on layaway until your next turn
Functionally, its identical to Dawnfeather Eagle, but the flavor of an angels arrival inspiring the troops makes much more sense to me than an eagles arrival (whose flavor text justifies its ability by it landing on Exquisite Archangels arm)