Thermonuclear reactor

{Lns}This spell can’t be countered.{Lns}Indestructible.{Lns} {Lns}As long as Thermonuclear reactor is untapped, each your spell that would more than three mana to cast costs three mana to cast.(For example, a spell that would cost {4}{B} to cast costs {2}{B} to cast instead, or spell that would cost {B}{B}{W}{2r}{x}{Pw} to cast costs {B}{B}{x} to cast instead on your choice.)