Underground Mortuary

({T}: Add {B} or {G}.)
Underground Mortuary enters the battlefield tapped.
When Underground Mortuary enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Lumra, Bellow of the Woods

Vigilance, reach
Lumra, Bellow of the Woods's power and toughness are each equal to the number of lands you control.
When Lumra enters, mill four cards. Then return all land cards from your graveyard to the battlefield tapped.

Command Tower

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

Arcane Signet

Meren of Clan Nel Toth

Whenever another creature you control dies, you get an experience counter.
At the beginning of your end step, choose target creature card in your graveyard. If that card's mana value is less than or equal to the number of experience counters you have, return it to the battlefield. Otherwise, put it into your hand.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. Llanowar Wastes deals 1 damage to you.

Woodland Cemetery

Woodland Cemetery enters the battlefield tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.