The River Frog

{1}: Put a Plague counter on The River Frog. You may cast and then exile an instant or sorcery spell from your graveyard with converted mana cost equal to or lower than the number of Plague counters on The River Frog without paying its
mana cost. Then, if The River Frog has ten or more Plague counters on it, sacrifice it and target player loses the game. Activate this ability only once p