Branching Bolt — ruling 1

You may choose just the first mode (targeting a creature with flying), just the second mode (targeting a creature without flying), or both modes (targeting a creature with flying and a creature without flying). You can’t choose a mode unless there’s a legal target for it.

Branching Bolt : règles, fonctionnement et interactions (MTG)

Branching Bolt 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

Choose one or both — • Branching Bolt deals 3 damage to target creature with flying. • Branching Bolt deals 3 damage to target creature without flying.

How it works : Branching Bolt

Original English text — Wizards of the Coast / Scryfall

#1October 1, 2008· Wizards of the Coast
You may choose just the first mode (targeting a creature with flying), just the second mode (targeting a creature without flying), or both modes (targeting a creature with flying and a creature without flying). You can’t choose a mode unless there’s a legal target for it.
No other card is named in this ruling.