Returning all nonland permanents you dont control is backbreaking to most opponents, and can often prevent opponents from mounting an effective comeback
1 Nashi, Moon Sage's Scion Is A Potent Rat Ninja Creature Nashi, Moon Sage's Scion is a rat ninja that can ninjutsu into play at the cost of three generic mana and one black mana
I even put my old Gishath, Suns Avatar EDH deck back together with the intent to upgrade it with cards from Lost Caverns
This is a victory condition that players can easily achieve with Evolution Sage that Proliferates during Landfall, adding one more counter of every kind of counter whenever Lands appear
Interestingly enough, all the Serpents in Magic refer to sea serpents, and not snakes
In the right deck, when cast at the right time, they can contort the game in your favor for relatively little mana