Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Haldan, Avid Arcanist

Partner with Pako, Arcane Retriever (When this creature enters, target player may put Pako into their hand from their library, then shuffle.)
You may play lands and cast noncreature spells from among cards you exiled that have fetch counters on them, and you may spend mana as though it were mana of any color to cast those spells.

Mountain

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Ketria Triome

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

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Pako, Arcane Retriever

Partner with Haldan, Avid Arcanist
Haste
Whenever Pako, Arcane Retriever attacks, exile the top card of each player's library and put a fetch counter on each of them. Put a +1/+1 counter on Pako for each noncreature card exiled this way.

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.

Rejuvenating Springs

Rejuvenating Springs enters tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

Command Tower

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

Exotic Orchard

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

Forest

Frontier Bivouac

Frontier Bivouac enters tapped.
{T}: Add {G}, {U}, or {R}.