When Forbidding Spirit enters, until your next turn, creatures can't attack you or planeswalkers you control unless their controller pays {2} for each of those creatures.
2019-01-25
Because it doesn't modify the characteristics of creatures, Forbidding Spirit's triggered ability can affect creatures that enter the battlefield after that ability resolves.
2019-01-25
Forbidding Spirit's effect continues until your next turn even if Forbidding Spirit leaves the battlefield before then.
2019-01-25
In a Two-Headed Giant game, creatures can attack your teammate and planeswalkers your teammate controls without requiring a mana payment.
2019-01-25
While Forbidding Spirit's effect is in effect, your opponents can choose not to pay to attack with a creature that attacks "if able." If there's no other player or planeswalker to attack, that creature simply doesn't attack.