Goblin Engineer

When this creature enters, you may search your library for an artifact card, put it into your graveyard, then shuffle.
{R}, {T}, Sacrifice an artifact: Return target artifact card with mana value 3 or less from your graveyard to the battlefield.

Gimbal, Gremlin Prodigy

Artifact creatures you control have trample.
At the beginning of your end step, create a 0/0 red Gremlin artifact creature token. Put X +1/+1 counters on it, where X is the number of differently named artifact tokens you control.

Esoteric Duplicator

Whenever you sacrifice this artifact or another artifact, you may pay {2}. If you do, at the beginning of the next end step, create a token that's a copy of that artifact.
{2}, Sacrifice this artifact: Draw a card.

Adrix and Nev, Twincasters

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
If one or more tokens would be created under your control, twice that many of those tokens are created instead.