Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Gruul Signet

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Selesnya Signet

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Tana, the Bloodsower

Trample
Whenever Tana, the Bloodsower deals combat damage to a player, create that many 1/1 green Saproling creature tokens.
Partner (You can have two commanders if both have partner.)

Bruse Tarl, Boorish Herder

Whenever Bruse Tarl, Boorish Herder enters the battlefield or attacks, target creature you control gains double strike and lifelink until end of turn.
Partner (You can have two commanders if both have partner.)

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.