Orim's Chant in exile (exiled by Isochron Scepter).
All permanents on the battlefield.
Steps
On each opponent upkeep activate Isochron Scepter to cast Orim's Chant targeting the player who's turn it is, preventing them from casting spells that turn.
Seedborn Muse untaps both Isochron Scepter and the mana required to activate it each turn.
Teferi, Mage of Zhalfir prevents your opponent from playing spells at instant speed before you are able to cast Orim's Chant or in response to Orim's Chant.
You may also pay the kicker cost to prevent them from attacking.