Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

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

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.