Kithkin Greatheart — ruling 1

If, after dealing first-strike combat damage, Kithkin Greatheart loses first strike (perhaps because the Giant you controlled was destroyed by first-strike combat damage), it won’t deal regular combat damage.

Kithkin Greatheart : règles, fonctionnement et interactions (MTG)

Kithkin Greatheart 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

As long as you control a Giant, this creature gets +1/+1 and has first strike.

How it works : Kithkin Greatheart

Original English text — Wizards of the Coast / Scryfall

#1June 7, 2013· Wizards of the Coast
If, after dealing first-strike combat damage, Kithkin Greatheart loses first strike (perhaps because the Giant you controlled was destroyed by first-strike combat damage), it won’t deal regular combat damage.
No other card is named in this ruling.