Savage Beating
Instant
Cast this spell only during combat on your turn.
Choose one —
• Creatures you control gain double strike until end of turn.
• Untap all creatures you control. After this phase, there is an additional combat phase.
Entwine 
(Choose both if you pay the entwine cost.)
Matt Thompson
This card will be released on 2025-09-26, it is not legal in any format until its release date approaches.
Rulings
The additional combat phase is directly after the combat phase in which Savage Beating is cast. There isn't a main phase between the two combat phases.
(wotc • 2004-12-01)
Rulings
The additional combat phase is directly after the combat phase in which Savage Beating is cast. There isn't a main phase between the two combat phases.
(wotc • 2004-12-01)