Cyrex, The Robot Dinosaur

Beep, Boop - Whenever another creature enters
the battlefield under your control, you may have
Cyrex gain +3/-3 or -3/+3 until end of turn.
Rawwwwr - Whenever another artifact enters the battlefield under your control, you may have it
become a 3/3 Robot Dinosaur artifact creature
until end of turn.
Here Bryant, here is your Robot Dinosaur...