Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)

This spell costs {2} less to cast if it targets a blue spell. Counter target spell unless its controller pays {3}.

Blackcleave Cliffs enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {B} or {R}.

Botanical Sanctum enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {G} or {U}.

Copperline Gorge enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {R} or {G}.

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

({T}: Add {G}.)

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

({T}: Add {U}.)

({T}: Add {R}.)

{T}: Add {U}. Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

{T}: Add {C}. {T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.