Ill look at each one and look for a better version of that card. Alpha Authority could be swapped for one of the sowrds.

Architect of the Untamed is too slow that could be a Emerald Medallion instead

Heron's Grace Champion is not that good here at all, i think Ambush Viper is better here. Surprise block and kill and ramp cause your cmdr

Hoofprints of the Stag is a really bad card in this deck. Not good here. Spirit Bonds would serve great as a replacement.

Myth Unbound will be a wasted card slot in this deck. Your cdr is indestructable. Its not going back to the command zone often enough , it could be Cathars' Crusade or Glimpse of Nature

Nantuko Cultivator would be a lot cooler if it was comboed with Splendid Reclamation, change it for Arena Rector.

Primitive Etchings not that good. Pair it up with Abundance it becomes really good. Eather take it out or add support for this card

Prowler's Helm could be one of the swords

Ranging Raptors is not good here without a way to abuse it. Swith with a Birds of Paradise

Rhys the Redeemed seems to me to be lost.

Swap Suspicious Bookcase for Key to the City

Take out Tolsimir Wolfblood for Collective Blessing

Trailblazer?...... bad switch for Anafenza, Kin-Tree Spirit

Waker of the Wilds is too slow, put Rude Awakening in its place

still needs to be made better

Nim Deathmantle only seems good on 2 or 3 creatures. I don't think it's good enough here. Without having some really good ETB effects like Acidic Slime and no free sac outlet its bad.

Im hoping to use the excess mana to save creatures with Nim Deathmantle

If multiple nontoken creatures are put into your graveyard from the battlefield at the same time, Nim Deathmantle’s second ability triggers that many times. You put the triggered abilities on the stack in any order, so you’ll determine in which order they resolve. If you pay 4 more than once, each card you paid 4 for will end up on the battlefield under your control, and Nim Deathmantle will end up attached to the last card that returned to the battlefield this way that it could equip.

Then replace it with Cauldron of Souls