Killer B

Ninjutsu {2}{u}{b} ({2}{u}{b}, Return an unblocked attacker you control to your hand: Put this card onto
the battlefield from you hand tapped and attacking.)
When Killer B deals combat damage to a player,
gain control of all Equipment that player
controls and attach them to Killer B.
If Killer B has 3 or more artifacts equipped to it,
you may exile it, then return it to the battlefield transformed under its owner's control.