The Anurid were originally beast creatures but were later errata'd to be frogs
You can then choose to cast them without paying their mana costs, and yes, you can also choose to stack all of the nonland spells in whatever manner you prefer
Green mages simply encourage them to do so in your direction
When selecting lands, consider the following: Aim for a land count that supports your deck's curve, typically around 3638 lands , adjusting based on your deck's mana requirements and ramp options
The Floodborn card is one of the Amber Lorcana cards in The First Chapter that helps players to find what they need from their deck, with the option to exert characters costing two ink or less to draw cards from your deck
Engle Sources: Abzan Ascendancy, Afterlife, Avacyn's Collar, Benevolent Offering, Bishop of Wings, Custodi Soulbinders, Dauntless Cathar, Doomed Traveler, Drogskol Cavalry, Elgaud Inquisitor...