At the beginning of your end step, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
4 /
4
--
Bountiful Promenade
Land
Bountiful Promenade enters the battlefield tapped unless you have two or more opponents.
{T}: Add {G} or {W}.
--
City of Brass
Land
Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.
--
Evolving Wilds
Land
{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Forest
Basic Land - Forest
({T}: Add {G}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Island
Basic Land - Island
({T}: Add {U}.)
{0}
Lotus Petal
Artifact
{T}, Sacrifice Lotus Petal: Add one mana of any color.
--
Mana Confluence
Land
{T}, Pay 1 life: Add one mana of any color.
--
Morphic Pool
Land
Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.
--
Plains
Basic Land - Plains
({T}: Add {W}.)
--
Plains
Basic Land - Plains
({T}: Add {W}.)
--
Reflecting Pool
Land
{T}: Add one mana of any type that a land you control could produce.
--
Rogue's Passage
Land
{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.
--
Sandsteppe Citadel
Land
Sandsteppe Citadel enters the battlefield tapped.
{T}: Add {W}, {B}, or {G}.
--
Scrubland
Land - Plains Swamp
({T}: Add {W} or {B}.)
--
Seaside Citadel
Land
Seaside Citadel enters the battlefield tapped.
{T}: Add {G}, {W}, or {U}.
--
Swamp
Basic Land - Swamp
({T}: Add {B}.)
--
Swamp
Basic Land - Swamp
({T}: Add {B}.)
--
Swamp
Basic Land - Swamp
({T}: Add {B}.)
--
Terramorphic Expanse
Land
{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
--
Tundra
Land - Plains Island
({T}: Add {W} or {U}.)
--
Vivid Creek
Land
Vivid Creek enters the battlefield tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from Vivid Creek: Add one mana of any color.
--
Vivid Grove
Land
Vivid Grove enters the battlefield tapped with two charge counters on it.
{T}: Add {G}.
{T}, Remove a charge counter from Vivid Grove: Add one mana of any color.
--
Vivid Marsh
Land
Vivid Marsh enters the battlefield tapped with two charge counters on it.
{T}: Add {B}.
{T}, Remove a charge counter from Vivid Marsh: Add one mana of any color.
--
Vivid Meadow
Land
Vivid Meadow enters the battlefield tapped with two charge counters on it.
{T}: Add {W}.
{T}, Remove a charge counter from Vivid Meadow: Add one mana of any color.