Spiraling Duelist — ruling 1

If Spiraling Duelist has double strike as the combat damage step begins, there will be a second combat damage step. As that second combat damage step begins, if Spiraling Duelist no longer has double strike (perhaps because an artifact creature you controlled was destroyed), Spiraling Duelist will not assign combat damage a second time.

Spiraling Duelist : règles, fonctionnement et interactions (MTG)

Spiraling Duelist 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

Metalcraft — This creature has double strike as long as you control three or more artifacts.

How it works : Spiraling Duelist

Original English text — Wizards of the Coast / Scryfall

#1June 1, 2011· Wizards of the Coast
If Spiraling Duelist has double strike as the combat damage step begins, there will be a second combat damage step. As that second combat damage step begins, if Spiraling Duelist no longer has double strike (perhaps because an artifact creature you controlled was destroyed), Spiraling Duelist will not assign combat damage a second time.
No other card is named in this ruling.