White uncommon that encourages relics, either directly or indirectly.
Let's start the voting!
Final Possessions –
Instant (U)Exile target creature. Its controller may search their library for an artifact card with converted mana cost less than or equal to that creature and put it onto the battlefield. If they can't find an artifact card, they may put a Relic artifact token onto the battlefield.
(Relics have no abilities.)"All we found was his most prized trinket, lying on his childhood bed."
—Diary of Fiona Darnielle, final entry Arms Refinement -
Enchantment
, Sacrifice a non-creature artifact with converted mana cost 3 or less: Put an Artifact Equipment token with "Equipped creature gets +1/+1" and "Equip
" onto the battlefield.
, Sacrifice a non-creature artifact with converted mana cost 3 or less: Put an Artifact Equipment token with "Equipped creature gets +3/+2 and has flying" and "Equip
" onto the battlefield.
Fire-Tender
Creature-human cleric (U)
Whenever an artifact enters the battlefield under your control, you may gain 2 life.
Tending the fire is the most sacred duty one can have.2/1
Scrap Fighter
Artifact Creature - Human Construct
~ gets +2/+0 as long as you control another artifact.
Sacrifice another artifact: Regenerate ~.
1/1
Creature - type
Flying
Sacrifice three artifacts: Exile target attacking or blocking creature.
3/2
Solar Offering InstantEach player sacrifices 2 nonland permanents.
Scrap Sculptor Creature - Human Artificer (U)
: Target noncreature artifact you control becomes a 3/3 artifact creature until end of turn.
"This is grassland under the ice, you know. Like Maraka. And even if the real animals left, mine are still here."2/2
Manjean Armorer Creature—Human Artificer (U)
Each Relic you control is an Equipment with equip
and "Equipped creature gets +2/+2."
"I don't know what these things were used for, but I know what I'd use 'em for."2/2
Shield of Shrapnel --
Instant (U)
As an additional cost to cast Shield of Shrapnel, sacrifice any number of artifacts.
Prevent the next X damage that would be dealt to you this turn, where X is the number of artifacts sacrificed this way. Shield of Shrapnel deals X damage to target creature or player.
Relic Guardian Creature - Angel (U)
Flying
Relic Guardian can block an additional creature for each Relic you control.
When Relic Guardian blocks, it gets +1/+1 until end of turn for each Relic you control.
3/3
Artifice Scrapper
Creature - Human [U]
Whenever a non-relic artifact is destroyed gain 2 life and put an artifact relic token under your control.
2/2
I vote for Steinhauser.