Beginning of Combat Step

From MTG Salvation Wiki

Turn Structure
Beginning Phase
Untap Step
Upkeep Step
Draw Step
Main Phase
Combat Phase
Beginning of Combat Step
Declare Attackers Step
Declare Blockers Step
Combat Damage Step
End of Combat Step
Main Phase
End Phase
End of Turn Step
Cleanup Step

From the Comprehensive Rules 307. Beginning of Combat Step 307.1. As the beginning of combat step begins, any abilities that trigger at the beginning of combat go on the stack. (See rule 410, “Handling Triggered Abilities.”) Then the active player gets priority and players may play spells and abilities.