Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When Thought Monitor enters, draw two cards.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

Myr Enforcer

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Chrome Mox

Imprint — When Chrome Mox enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Village Bell-Ringer

Flash (You may cast this spell any time you could cast an instant.)
When Village Bell-Ringer enters, untap all creatures you control.

Helga, Skittish Seer

Whenever you cast a creature spell with mana value 4 or greater, you draw a card, gain 1 life, and put a +1/+1 counter on Helga, Skittish Seer.
{T}: Add X mana of any one color, where X is Helga, Skittish Seer's power. Spend this mana only to cast creature spells with mana value 4 or greater or creature spells with {X} in their mana costs.

Frogmite

Sojourner's Companion

Affinity for artifacts
Artifact landcycling {2} ({2}, Discard this card: Search your library for an artifact land card, reveal it, put it into your hand, then shuffle.)