Firebending is a keyword ability, adding mana during attacks that lasts until the end of combat
CORI-JP046 Chaos Silk Hat (Chaos Hats) Quick-Play Spell (1) When your opponent activates a Normal Spell/Trap Card, or monster effect: Choose 3 Spells/Traps with different names from each other from your Deck and 1 monster in your Main Monster Zone that mentions Ritual of Light and Darkness, and if you do, Special Summon the chosen Spells/Traps as Normal Monsters (Spellcaster/DARK/Level 8/ATK 0/DEF 0) whose name is Chaos Hats in face-down Defense Position, Set the chosen monster, and shuffle them on the field, then your opponents activated effect becomes destroy 1 opponents Set monster
Multiplications and divisions, including halving/doubling, are not affected.) C Common
Garruk, Wrath of the Wilds Spellbook Underdark Basilisk Wary Okapi Nessian Hornbeetle Pestilent Wolf Murasa Rootgrazer Sylvan Brushstrider Ferocious Pup Dawntreader Elk Trufflesnout Barkhide Troll Scurrid Colony Territorial Scythecat Garruk's Uprising Dire Wolf Prowler Mosscoat Goriak For a 4-mana planeswalker all of these spellbook options are pretty underwhelming
This is very much a build-around card, but it also slides neatly into Glarb lists as pure value