Dictate of Karametra

Flash
Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Zhur-Taa Ancient

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Untap this artifact during each other player's untap step.
{T}: Add one mana of any color.

{T}: Choose a player. That player adds one mana of any color they choose.

Vigilance
A player losing unspent mana causes that player to lose that much life.
{1}, {T}: Each player adds {B}{R}{G}.

Untap all permanents you control during each other player's untap step.