Sundering mastery

Sundering mastery costs {r} less for each land that has left the battlefield this turn
Choose two
• Deal 4 damage to target creature or planeswalker
• Deal 2 damage to all creatures, and each opponent
• Return target land card that has entered the graveyard this turn into play under your control
{bull} Up to 2 target instant or sorcery spells in your graveyard gain flashback until end of turn