Forest: Haunted Weave, Perfect Aim, Root Trap, Nature’s Aura, Wall of Vines, Elven Sentries, Harvest Moon
Water: Snap Freeze, Insulated, Ocean’s Trident, Watery Binding, Deluge, Water Mastery, Aquatic Glory
Fire: Feline Fury, Fireproof, Up in Flames, Firestarter, Gift of Fire, Firebringer, Fireblade
Fire Brand: Gain 1 Attack for each Red ally.
18 x Minor Fire, 10 x Runic Fire, 10 x Runic Nature
Fireproof: Immunity to Burning and Faerie Fire.
26 x Minor Fire, 12 x Major Fire, 10 x Arcane Beast
Heatwave: Create a Firestorm at the start of every turn.
34 x Minor Fire, 6 x Arcane Beast, 2 x Celestial
Flame Soul Mythic
Mana cost: 14
Choose a Mana Gem. Deal [Magic + 1] damage to each enemy of that color and Burn them. Give all allies of the matching color 4 Attack.
The Fireproof ability could be potentially repeated or mixed with a Hero Fireproof trait.
The Firebringer ability and Heatwave is practically almost the same thing.
So, if possible, I am suggesting adding another immunity to the Tree.
Also, I am suggesting that if you use the Firebringer ability and Heatwave trait together, that you should automatically get to create the Red Madness Storm, which is a new recent feature.