Nesting Bot

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
When this creature dies, create a 1/1 colorless Servo artifact creature token.
Max speed — This creature gets +1/+0.

Brightglass Gearhulk

First strike, trample
When this creature enters, you may search your library for up to two artifact, creature, and/or enchantment cards with mana value 1 or less, reveal them, put them into your hand, then shuffle.

Dusk Rose Reliquary

As an additional cost to cast this spell, sacrifice an artifact or creature.
Ward {2}
When this artifact enters, exile target artifact or creature an opponent controls until this artifact leaves the battlefield.

Sheltered by Ghosts

Enchant creature you control
When this Aura enters, exile target nonland permanent an opponent controls until this Aura leaves the battlefield.
Enchanted creature gets +1/+0 and has lifelink and ward {2}.

Teething Wurmlet

This creature has deathtouch as long as you control three or more artifacts.
Whenever an artifact you control enters, you gain 1 life. If this is the first time this ability has resolved this turn, put a +1/+1 counter on this creature.