Sphinx of the Second Sun
Creature — Sphinx
At the beginning of each of your postcombat main phases, there is an additional beginning phase after this phase. (The beginning phase includes the untap, upkeep, and draw steps.)
Legal in
Legacy, Vintage, Commander
Rulings (6)
If multiple phases are added to the same point in your turn, the most recently created phase happens first. For example, say you control Sphinx of the Second Sun and its ability triggers during your postcombat main phase. Later during that same main phase, another effect gives you an additional combat phase after this main phase. The additional combat will happen first, followed by the additional beginning phase.
2020-11-10
The additional beginning phase will be a lot like your normal beginning phase. During the untap step, permanents will phase in or out as appropriate and you'll untap your tapped permanents. Anything that triggers "at the beginning of your upkeep" or similar will trigger during the upkeep step, and you'll eventually draw a card for your draw step.
2020-11-10
After the additional beginning phase, the game proceeds to the ending phase (unless something has added even more phases; see below.)
2020-11-10
Even if you don't attack with any creatures during combat, you'll still get a postcombat main phase and Sphinx of the Second Sun's ability will still trigger.
2020-11-10