Arcane Signet

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

Bjorna, Nightfall Alchemist

{T}, Sacrifice an artifact: Bjorna, Nightfall Alchemist deals 1 damage to target creature. Goad that creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Partner—Friends forever (You can have two commanders if both have this ability.)

Sol Ring

Growth Spiral

Draw a card. You may put a land card from your hand onto the battlefield.

Mountain

Command Tower

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Frontier Bivouac

This land enters tapped.
{T}: Add {G}, {U}, or {R}.

Academy Manufactor

If you would create a Clue, Food, or Treasure token, instead create one of each.

Island

Counterspell

Elmar, Ulvenwald Informant

Haste
Whenever you cast your second spell each turn, untap target creature, then investigate. (Create a colorless Clue artifact token with "{2}, Sacrifice this artifact: Draw a card.")
Partner—Friends forever (You can have two commanders if both have this ability.)

Forest

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Hinterland Harbor

This land enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.