Jaspera Sentinel

Reach
{T}, Tap an untapped creature you control: Add one mana of any color.

Citanul Hierophants

Creatures you control have "{T}: Add {G}."

Enduring Vitality

Vigilance
Creatures you control have "{T}: Add one mana of any color."
When Enduring Vitality dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Kona, Rescue Beastie

Survival — At the beginning of your second main phase, if Kona, Rescue Beastie is tapped, you may put a permanent card from your hand onto the battlefield.

Citanul Stalwart

{T}, Tap an untapped artifact or creature you control: Add one mana of any color.