{X}{1}: Chimeric Coils becomes an X/X Construct artifact creature. Sacrifice it at the beginning of the next end step.
A noncreature permanent that turns into a creature can attack, and its {T} abilities can be activated, only if its controller has continuously controlled that permanent since the beginning of their most recent turn. It doesn’t matter how long the permanent has been a creature.
If X is 0, Chimeric Coils becomes a 0/0 creature and is put into its owner’s graveyard.