Zenith Chronicler

Whenever a player casts their first multicolored spell each turn, each other player draws a card.

Forest

Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

Chief of the Foundry

Other artifact creatures you control get +1/+1.

Collected Company

Look at the top six cards of your library. Put up to two creature cards with mana value 3 or less from among them onto the battlefield. Put the rest on the bottom of your library in any order.

Iron Apprentice

This creature enters with a +1/+1 counter on it.
When this creature dies, if it had counters on it, put those counters on target creature you control.

Metallic Mimic

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

Patchwork Automaton

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever you cast an artifact spell, put a +1/+1 counter on this creature.

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Hangarback Walker

This creature enters with X +1/+1 counters on it.
When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on this creature.
{1}, {T}: Put a +1/+1 counter on this creature.

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.