Hellfire Warlock

Description
The hellfire warlocks are a secretive group of specialist warlocks who have mastered hellfire, a dangerous energy found only in the Nine Hells. By tapping into this infernal power, these characters learn to infuse their eldritch blasts and magic items that they wield with the dark power of hellfire. A character can achieve a maximum of 3 levels in the Hellfire warlock prestige class.

Requirements
Skills: Intimidate 6, Lore: The Planes 12, Spellcraft 6

Spellcasting: Must have Brimstone Blast or Hellrime Blast

Invocations
At each level, you gain new invocations known and an increase in invoker level as if you had also gained a level in the warlock class. You do not, however, gain any other benefit a character of that class would have gained.

Hellfire Blast
Whenever you use your Eldritch blast ability, you can change your Eldritch blast into a hellfire blast. A hellfire blast deals your normal Eldritch blast damage plus an extra 2d6 points of damage per class level. If your blast hits multiple targets (for example, the Eldritch chain or Eldritch cone blast shape invocations), each target takes the extra damage. This damage is not fire damage. Hellfire burns hotter than any normal fire.

Each time you use this ability, you take 1 point of Constitution damage. This is mainly because of the dangerous nature of Hellfire this supernatural flame burns your enemies flesh and soul, but also takes a little of you as well. If you do not have a Constitution score or are somehow immune to Constitution damage, the ability remains usable.

Resistance to Fire
At 2nd level, you gain resistance to fire 10. This resistance stacks with any resistance to fire you have gained from warlock class levels.

Summon Baatezu
Once per day, the Hellfire Warlock can randomly summon a Baatezu from the Nine Hells to fight for the party. Control of the Baatezu lasts for a number of rounds equal to 1 round per hellfire warlock level + 1d8 + their Charisma bonus. When the ability expires, the caster loses dominance over the Baatezu - which can have disastrous consequences, as devils typically despise being bothered by lesser beings. The caster is advised not to leave this up to chance, and dispel this summons before this time is up, sending the Baatezu back to the Nine Hells - though the devil might not attack, this method is the only certain way of avoiding a violent confrontation with the angry creature.

Hellfire Shield
You can call up hellfire to surround yourself with a protective barrier. Whenever someone directs a melee attack against you, you can, as an immediate action, aim a blast of hellfire at that creature. This blast deals damage equal to your eldritch blast (including bonus damage from the hellfire blast ability). This blast automatically strikes the target, which can attempt a Reflex saving throw for half damage (DC 10 + 1/2 your character level + your Cha modifier).

Each time you use this ability, you take 1 point of Constitution damage. This is mainly because of the dangerous nature of Hellfire this supernatural flame burns your enemies flesh and soul, but also takes a little of you as well. If you do not have a Constitution score or are somehow immune to Constitution damage, the ability remains usable.

Gameplay notes
Both Hellfire Blast and Hellfire Shield are "play modes", in a similar vein to, for instance, Power Attack. This means you do not have to enable them at all times.

This also means that you can apply an essence and shape to your eldricht blast as you would normally do (for instance, Eldricht Chain, Hellrime Blast).

Finally, it should be noted that the constitution damage only applies if you actually hit a target: if for instance you cast an Eldricht Doom where there is no foe to hit, the constitution damage will not apply.