Nyxbloom Ancient

Trample
If you tap a permanent for mana, it produces three times as much of that mana instead.

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Leafkin Druid

{T}: Add {G}. If you control four or more creatures, add {G}{G} instead.

Ancient Greenwarden

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Omnath, Locus of Mana

You don't lose unspent green mana as steps and phases end.
Omnath, Locus of Mana gets +1/+1 for each unspent green mana you have.