Hellfire Greataxe

Hellfire Greataxe is a very rare +2 Greataxe that deals additional Fire damage, afflicts its wielder with Heat on each successful hit, and grants the Hellflame Cleave weapon action.

Anything hit by this has the life expectancy of a glass hammer.

Properties

Damage: 1d12 + 2 (3~14) + Strength modifier ⁠Slashing
Extra damage: 1d6 (1~6) ⁠Fire
Details:  Greataxes;  Rarity: Very rare; Enchantment: + 2;  Two-Handed;  Melee: 1.5 m / 5 ft;  Weight: 3.15 kg / 6.3 lb;  Price: 960 gp; UID
MAG_WATCHER_Human_Greataxe

UUID
dd0e9fa2-e012-454d-9f2d-53c0a0776015

Stats
MAG_WATCHER_Human_Greataxe

Special

The holder of this item gains:

Thermodynamo: Whenever you deal damage with this weapon, you gain 2 turns of  Heat.

Weapon actions

If you have proficiency, equip in main hand to gain:

 Cleave (): Swing your weapon in a large arc to attack up to 3 enemies at once. They each take half the damage your weapon usually deals. ( Recharge: Short rest.)

 Lacerate (): Slash at your target's vital points to make it Bleed. ( Recharge: Short rest.)

 Prepare (): Spend 6 m / 20 ft of your movement to deal an additional [Strength modifier]PhysicalDRS damage (minimum 1) on each successful weapon attack for the rest of the turn. ( Recharge: Short rest.)

Special weapon actions

This weapon also grants the following:

 Hellflame Cleave (): Cast as a cantrip ( Recharge: Short rest.)

Sorcerous Vault X: 366 Y: 941: In a gilded chest in the "Illusion" section

Once in the vault, upon finding the named doors, the party must go through the "Silverhand" door and in the next area destroy the door labeled "Illusion" (trying to enter the door normally will not work). Through the door is the room with the chest.
This is one of very few non-Dippable weapons in the game, as its special property functions largely the same as being dipped in  Fire.
It is not listed in-game, but Thermodynamo can only activate once per attack, even when hitting multiple targets with Cleave or similar abilities.

Regarding Thermodynamo:

It is not listed in-game, but Thermodynamo can only activate once per attack, even when hitting multiple targets with Cleave or similar abilities.

Regarding Hellflame Cleave:

This weapon action does not count as an attack for the purposes of  Extra Attack and requires a full  Action to use.
Instead, this is actually classified as a cantrip which results in some unexpected interactions.
- It can be  Counterspelled.
- A sorcerer can apply Metamagic to it. The applicable options are  Careful Spell,  Extended Spell,  Heightened Spell,  Subtle Spell, and perhaps most importantly,  Quickened Spell.
- It benefits from spell and cantrip specific damage bonuses like  Elemental Affinity: Damage and  Necklace of Elemental Augmentation.
- It activates Eldritch Knight's  War Magic.
- It can still be cast while  Silenced.
The Roiling Hellfire condition is applied by both the weapon action itself and the  Hellfire surface it creates. Even if a target saves against the attack, it will still be inflicted with Roiling Hellfire cause by the surface.

This weapon has a hidden condition MAG_FIRE_DIPPED_HELLFIRE which is supposed to make its 1d6⁠⁠Fire damage ignore fire resistance. Additionally, Hellflame Cleave and the Hellfire surface it creates are also both supposed to ignore fire resistance. Neither of these effects are currently ignoring fire resistance.

Regarding Hellflame Cleave:

Despite the tooltip saying that Hellfire ignores resistances and immunities, it does not.
Since this attack does not involve an attack roll, it does not benefit from certain bonus damage sources which check the attack roll type despite listing the additional damage on the tooltip. These include:

Hellfire Greataxe