Abilities that trigger “at end of combat” trigger as the end of combat step begins. Effects that last “until end of combat” expire at the end of the combat phase.
January 25, 2019 · Ravnica Allegiance
Abilities that trigger "at end of combat" trigger as the end of combat step begins. Effects that last "until end of combat" expire at the end of the combat phase.
November 11, 2016 · Commander 2016
Abilities that trigger “at end of combat” trigger as the end of combat step begins. Effects that last “until end of combat” expire at the end of the combat phase.
September 30, 2016 · Kaladesh
Abilities that trigger “at end of combat” trigger as the end of combat damage step begins. Abilities that last “until end of combat” expire at the end of the combat phase.
February 1, 2010 · Worldwake
Second, the active player gets priority. Players may cast spells and activate abilities.