Tarnation Vista

This land enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.
{1}, {T}: For each color among monocolored permanents you control, add one mana of that color.

The Big Score

Tarnation Vista enters the battlefield tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.
{1}, {T}: For each color among monocolored permanents you control, add one mana of that color.

Tarnation Vista’s last ability is a mana ability. It doesn’t use the stack and can’t be responded to.

The five colors are white, blue, black, red, and green, and as such, Tarnation Vista’s last ability can produce five mana at most.