Mirrorworks

Artifact

Whenever another nontoken artifact enters the battlefield under your control, you may pay . If you do, create a token that's a copy of that artifact.

2011-06-01:
Each time the ability triggers, you can pay {2} only one time to get one token.
2011-06-01:
As the token is created, it checks the printed values of the artifact it’s copying, as well as any copy effects that have been applied to it.
2011-06-01:
The copiable values of the token’s characteristics are the same as the copiable values of the characteristics of the artifact it’s copying.
2011-06-01:
If the artifact that caused Mirrorworks’s ability to trigger has already left the battlefield by the time the ability resolves, you can still pay {2}. If you do, you’ll still put a token onto the battlefield. That token has the copiable values of the characteristics of that nontoken artifact as it last existed on the battlefield.