Noxious Grasp — ruling 1

If the target creature or planeswalker is an illegal target by the time Noxious Grasp tries to resolve, the spell doesn’t resolve. You won’t gain life. If the target is legal but not destroyed (most likely because it has indestructible), you will gain life.

Noxious Grasp : règles, fonctionnement et interactions (MTG)

Noxious Grasp 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

Destroy target creature or planeswalker that's green or white. You gain 1 life.

How it works : Noxious Grasp

Original English text — Wizards of the Coast / Scryfall

#1July 12, 2019· Wizards of the Coast
If the target creature or planeswalker is an illegal target by the time Noxious Grasp tries to resolve, the spell doesn’t resolve. You won’t gain life. If the target is legal but not destroyed (most likely because it has indestructible), you will gain life.
No other card is named in this ruling.