Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Dimir Signet

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Chromium

Flying
Rampage 2 (Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it beyond the first.)
At the beginning of your upkeep, sacrifice Chromium unless you pay {W}{U}{B}.

Azorius Signet

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Stormscape Familiar

Flying
White spells and black spells you cast cost {1} less to cast.

Orzhov Signet

Marble Diamond

This artifact enters tapped.
{T}: Add {W}.