At the beginning of each player's draw step, Omen Machnie triggers, exiling the top card of that player's library and allowing them to cast it, if able.
Teferi only allows opponent to cast spells at sorcery speed, thus forbidding them from playing the card exiled by
Omen Machine, unless it is a land card.
Results
Opponents can only play lands exiled by
Omen Machine.
Players can't draw cards.
Mass Land Denial.
Metadata
Lock
Bracket tag
RuthlessBracket 4+
For competitive decks at brackets 4+
1
2
3
4
5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.