Build Advice, Beguiler/Fiendblooded

[Andurian]

My DM has some specific leveling rules. The key one that is making me consider some options is the fact that you must level a Prestige Class to completion, no dips.

Thematically, I want to be a Beguiler/Fiendblooded. I could just go straight Beguiler and call it a day, and use the cross-class skill points to get the skills I need. I could also take Able Learner (I am a Human) and do it that way. I lose a feat, however...

I also was debating on going Ruathar (Elf-Friend) for three levels and get the skills I needed that way. I would lose a total of 6 skill points.... which should be made up easily by the fact I would need to use an additional 8 in cross class knowledge. Depending on how I time it, I may lose the Advance Learning as well.

What would be a good way to do this? Once again, no Prestige Class dips.

Also, how effective is Wither Limb as a spell? I was wondering if it would be worth it (seems amusing in my head) to chain it to effect a lot of enemies.

Is there an easy way to lower the metamagic cost of Silent Spell? I was debating on making all my spells silent if I found a way to lower it easily and cheaply.

[Psyren]

The Education feat will get you Know (Planes.) It's a good idea anyway since it gets you all the Knowledge skills and you're an Int-based caster. Knowledge Devotion is another way.

Concerning Silence - Races of Stone 133 has rules to let you mask your verbal/somatic components by "casting up your sleeve." All you need is a Sleight of Hand check and you can cast unobtrusively.

[Khedrac]

iirc the only problem skill is Knowledge: Planes - and for that there is an Abyssal Heritor feat in the Fiendish Codex I which makes it a class skill.
If I have misremembered it still covers one of the skills you need.

[Andurian]

These ideas work and I'll consider them. I did realize Able Learner wont work though. That wouldn't let me get the 8 ranks til much later.

Not sure if I want to use up the feat though, which is partly why I was considering Ruathar to begin with (a single dip would have covered this) Continues spell progression and some minor bonuses. Still not too sure though.

Thanks for the Sleight of Hand trick. Kinda makes Silent and Still spell seem kinda pointless.... would help when restrained or deafened though.

[Psyren]

The SoH trick is really only an option for Beguilers (and maybe Bards) anyway, so it's hardly a gamebreaker. SoH is trained only and is cross-class for most casters.

Ruathar is a nice option because it delays your advanced learning without costing you too much Fiendblooded progression (since it's so short.) So if you can swing/waive the fluff requirement then consider it. I was just presenting alternatives.