#1 trick: any of the Trickster classes out of Complete Scoundrel and/or Bloodlines from UA will increase the hellfire blast ability.
It's just the uncanny trickster that has advancement for any class feature, isn't it?
The bloodlines seem like they aren't really worth it for the amount you'd have to spend on them. When you cango human and gain a extra feat and 4 extra skill points.
Since they're added onto whatever race you already have, it's not like you have to miss out on the regular human benefits. But what you really gain in this case (as draco indicated) is being able to count the bloodline levels when calculating any character ability based on class levels.
In this case, that allows you to count as having more than the usual limit of three class levels of hellfire warlock when calculating the power of a hellfire blast (which adds 2d6 damage per class level).
community.wizards.com/go/thread/view/758...
The bloodline thing is from Unearthed Arcana, and yes, you can be a human with a Greater Vampire Bloodline and get all the goodies from both, you effectively lose a bit less than 3 levels worth of XP and can choose when you lose it. The loss of HP can be a real problem especially in early levels so do it cautiously, most of your other losses will be made up for by the bloodline abilities.
Since you need 12 ranks in Knowledge the Planes to even become a Hellfire Warlock look into a build that gets the first level of Uncanny Trickster and or Legacy Champion before you enter Hellfire Warlock, also grab that Binder level early as well. Tempest built something like this one time.
Binder 1/Warlock 6/Uncanny Trickster 1/Legacy Champion 1/Hellfire Warlock 3/+5 Legacy Champion/+2 Uncanny Trickster/+1 Warlock
He used Illumian for the improved CL which ups your damage. Sigils were Vaul and Krau.
This build needed a 14 Int and focused mostly on Dex after that, Cha and Con coming nect in priority, it dumped Str and Wis.
Feats included Martial Study (for Leading the Attack), Weapon Finesse, Combat Reflexes, Enhanced Power Sigils, Goad, Martial Study (Defensive Rebuke), Martial Stance (Thicket of Blades)
Effectively this is an AOO tank build that uses a big bad eldritch glaive for damage, and Beguiling Influence along with the Diplomacy as a class skill thing to be a party Face as well.
Best of luck.
Martial Study (for Leading the Attack), Weapon Finesse, Combat Reflexes, Enhanced Power Sigils, Goad, Martial Study (Defensive Rebuke), Martial Stance (Thicket of Blades)
Effectively this is an AOO tank build that uses a big bad eldritch glaive for damage, and Beguiling Influence along with the Diplomacy as a class skill thing to be a party Face as well.
In the Trickster/Champion Overdrive build the AOO tank loadout was used to provide close area combat control as well as more hits/turn with the gigantic 28d6 eldritch glaive.
Nub question, how does trickster and champion raise hellfire warlock?
To cover it again in brief (you can go back and read the details in other responses in this thread); they both can count for abilities based on class level, and the hellfire warlock's extra damage on a hellfire blast is +2d6 points per class level.
For example, three levels of uncanny trickster gives you two levels of class advancement (there's one "dead" level), so if you've got three levels of hellfire warlock as well, you can count as having five levels of hellfire warlock and deal an extra 10d6 points of damage with your hellfire blast, instead of 6d6 extra points.
Seriously, dood? It's spelled out for you in TWO of Andarious' posts. Martial Study is the feat; Leading the Attack is the name of the maneuver taken with the feat. Please try to keep up.
I get it now :-) so if I had 1 trickster and 6 legacy that'd be 7 bonus with the 3 bloodline making a huge 10 just from them
That's almost right, except that the very first level of uncanny trickster (and the 1st and 7th levels of the legacy champion) don't give any advancement for class features.
Bloodlines don't have any "dead" levels like that, but they also don't give you any additional Hit Dice.
Maneuvers & stances are all in ToB. The ones Tempest chose are Devoted Spirit & White Raven disciplines.
"ToB" is the Tome of Battle, Shinigami, if you're not up on our abbreviations.
I picked White Raven's Douse the Flames there not because the maneuver's useful at all (well, it is, just not for you) but rather because it gave Diplomacy as a class skill from level 1. You can use that with a binder's pact with Naberius (which you'll be taking to protect yourself as a hellfire warlock later anyway) and the warlock's Beguiling Influence invocation to become a pretty powerful public speaker and negotiator at a low level. You don't need to invest anything extra besides that in order to remain your party's spokesman even as you focus on your hellfire. And besides, the charismatic fiend is a staple of fiction (ever read Faust?)
The Devoted Spirit maneuvers are there for Thicket of Blades, a lynchpin of the "AoO Tank" style of play, which that particular glaivelock build uses in an unusual manner (normally, AoO tanks focus on getting AoOs in response to everything their opponents do, and spend those attacks to prevent their opponents from doing it. You just use those attacks as extra chances to smack with a nearly 30d6 glaive.) For more information on this style of play, I wrote an introduction to it here (click the spoiler block at the bottom). A good AoO tank is a fun and very useful way to play a melee warrior in 3.5, and it isn't entirely obvious to new players that such a character is even possible.
I'm guessing the reason you take UT 1 is that there are fewer prereqs and/or that UT has class skills or something similar that helps with Legacy Champion prereqs.
There's many reasons for this. It's not harder to qualify for, but it works best if you take UT first. Uncanny Trickster has all skills as class skills, and Legacy Champion's class skills consist of a small list of skills, plus any class skills from all of your other classes. Put 'em together and you get Factotum-grade skill lists, albeit with less Int synergy and fewer base skill points.
Also, taking Uncanny Trickster 1 and Legacy Champion 1 before you can qualify for your PrC (here, Hellfire, which requires 12 ranks in a specific skill - and Legacy Champion requires Character Level 10, so I think I botched the timing a bit here) allows you to enter your PrC right on schedule, and then continue to advance it afterwards without any delays (since you crossed those non-advancing levels on your way to the PrC). You finish Hellfire as early as possible, and then take UT 2, which advances Hellfire right away instead of having to wait a level while you take UT 1.
I openly admit that the build suggested there is subpar; it's just there as an example.
Finally, HappyShinigami, I would strongly suggest avoiding things like bloodlines or even hellfire warlock if you're this new to the game. Certain things require a degree of familiarity with the rules in order to work, or work well, and those are among them.
There's many reasons for this. It's not harder to qualify for, but it works best if you take UT first. Uncanny Trickster has all skills as class skills, and Legacy Champion's class skills consist of a small list of skills, plus any class skills from all of your other classes. Put 'em together and you get Factotum-grade skill lists, albeit with less Int synergy and fewer base skill points.
It doesn't quite have all skills as class skills; it lacks Concentration, Diplomacy, Handle Animal, Heal, Knowledge, Ride, Speak Language, Spellcraft, and Survival, in addition to any of the skills that aren't on the general list (like Autohypnosis). The Uncanny Trickster has a good list, but not a complete one.
It's not really a case of needing the specific skills; the base warlock class gives you the class skills you need for the Hellfire Warlock, and the level in binder gives you some Knowledge (history) for the Legacy Champion. It's certainly nice to have some extra skills available, but it's not an absolute requirement.