Vona, Butcher of Magan — ruling 1

Vona's last ability can be activated during any step or phase of your turn, including the combat phase. It's possible to attack with Vona and then activate its ability before blockers are declared. Doing so won't remove Vona from combat.

Vona, Butcher of Magan : règles, fonctionnement et interactions (MTG)

Vona, Butcher of Magan is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Vigilance, lifelink , Pay 7 life: Destroy target nonland permanent. Activate only during your turn.

How it works : Vona, Butcher of Magan

Original English text — Wizards of the Coast / Scryfall

#1September 29, 2017· Wizards of the Coast
Vona's last ability can be activated during any step or phase of your turn, including the combat phase. It's possible to attack with Vona and then activate its ability before blockers are declared. Doing so won't remove Vona from combat.
No other card is named in this ruling.