Mosstodon — ruling 1

The ability checks the targeted creature’s power twice: when the creature becomes the target, and when the ability resolves. Once the ability resolves, it will continue to apply to the affected creature no matter what its power may become later in the turn.

Mosstodon : règles, fonctionnement et interactions (MTG)

Mosstodon 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

: Target creature with power 5 or greater gains trample until end of turn.

How it works : Mosstodon

Original English text — Wizards of the Coast / Scryfall

#1October 1, 2008· Wizards of the Coast
The ability checks the targeted creature’s power twice: when the creature becomes the target, and when the ability resolves. Once the ability resolves, it will continue to apply to the affected creature no matter what its power may become later in the turn.
No other card is named in this ruling.