Zacama, Primal Calamity — ruling 1

Zacama's damage-dealing ability can be activated during combat, perhaps targeting a creature blocking it. If all creatures blocking Zacama are destroyed, its combat damage is assigned to the player, planeswalker, or battle it's attacking because of trample. If the blocking creatures are dealt nonlethal damage, that damage is considered when assigning trample damage.

Zacama, Primal Calamity — ruling 2

Zacama's triggered ability triggers if you cast it from any zone. It doesn't trigger if you put Zacama onto the battlefield without casting it.

Zacama, Primal Calamity : règles, fonctionnement et interactions (MTG)

Zacama, Primal Calamity 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

Reach, vigilance, trample When Zacama enters, if you cast it, untap all lands you control. : Zacama deals 3 damage to target creature. : Destroy target artifact or enchantment. : You gain 3 life.

How it works : Zacama, Primal Calamity

Original English text — Wizards of the Coast / Scryfall

#1July 28, 2023· Wizards of the Coast
Zacama's damage-dealing ability can be activated during combat, perhaps targeting a creature blocking it. If all creatures blocking Zacama are destroyed, its combat damage is assigned to the player, planeswalker, or battle it's attacking because of trample. If the blocking creatures are dealt nonlethal damage, that damage is considered when assigning trample damage.
No other card is named in this ruling.
#2January 19, 2018· Wizards of the Coast
Zacama's triggered ability triggers if you cast it from any zone. It doesn't trigger if you put Zacama onto the battlefield without casting it.
No other card is named in this ruling.