Legion's Landing // Adanto, the First Fort — ruling 1

Once you've attacked with three or more creatures, Legion's Landing will transform even if some of those creatures leave the battlefield or are removed from combat.

Legion's Landing // Adanto, the First Fort — ruling 2

The last ability of Legion's Landing only counts creatures that you declare as attacking creatures. Creatures that enter the battlefield attacking won't count.

Legion's Landing // Adanto, the First Fort : règles, fonctionnement et interactions (MTG)

Legion's Landing // Adanto, the First Fort 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

When Legion's Landing enters, create a 1/1 white Vampire creature token with lifelink. When you attack with three or more creatures, transform Legion's Landing. (Transforms from Legion's Landing.) : Add . , : Create a 1/1 white Vampire creature token with lifelink.

How it works : Legion's Landing // Adanto, the First Fort

Original English text — Wizards of the Coast / Scryfall

#1September 29, 2017· Wizards of the Coast
Once you've attacked with three or more creatures, Legion's Landing will transform even if some of those creatures leave the battlefield or are removed from combat.
No other card is named in this ruling.
#2September 29, 2017· Wizards of the Coast
The last ability of Legion's Landing only counts creatures that you declare as attacking creatures. Creatures that enter the battlefield attacking won't count.
No other card is named in this ruling.