Border Guardian — ruling 1

Playing a land won’t cause any of Border Guardian’s abilities to trigger. But for the record, Unstable basic lands don’t have a border.

Border Guardian : règles, fonctionnement et interactions (MTG)

Border Guardian 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

Whenever you cast a silver-bordered spell, put a +1/+1 counter on this creature. Whenever you cast a black-bordered spell, this creature can't be blocked this turn. Whenever you cast a white-bordered spell, this creature gains double strike until end of turn.

How it works : Border Guardian

Original English text — Wizards of the Coast / Scryfall

#1January 19, 2018· Wizards of the Coast
Playing a land won’t cause any of Border Guardian’s abilities to trigger. But for the record, Unstable basic lands don’t have a border.
No other card is named in this ruling.