[3.5] Making a gestalt dragon villain

[Myou]

I want to make a black dragon my PCs beat up recently into a recurring foe.
The PCs are level 7, but can easily manage much higher CR enemies, so I normally treat them at level 10+ for making encounters. There are three PCs, all gestalt, a wizard//archivist, a warblade//scout and a wizard//passive homebrew class. All three use a fair bit of homebrew material here and there.
The warblade does lots of melee damage and the other two blast/buff/heal.

I want to make this black dragon into a gestalt (that's dragon//class levels or templates) villain that can really challenge them, something in the "Run for it!" area, but not 'rocks fall'.

So what should I make? Feats, classes, templates? All books are available.

One point of note is that he wants revenge, and wants to take it personally, so he needs to be able to handle the warblade in solo melee combat.

[Eldariel]

Cleric of Tiamat to supercharge his spellcasting, and pump the melee? Some extra actions would be nice so if you don't care about the dual progression crap, RKV could be nice. Alternatively, stat stack as Dragon stats tend to be high.

[Zore]

Making him a dread Necromancer on the other side of his dragon levels could be very useful and let him have an entire army to back him up.

[The Shadowmind]

I'd go with a adult, Xorvintaal(MM V, template) Black Dragon, with Twist of Fate ability, and then the Rejuvenation ability(Makes him make a chance of being a recurring Lillian as well(adds +1 CR for a second ability, don't add or pick something else if he is a one shot boss). Have the other half of the gestalt be factotum.

[TheThan]

I was going to suggest a Half dragon, dragon blooded dragonwrought kolbold, dragon shaman. But I guess you already have an idea for your dragon villain.

[Myou]

Cleric of Tiamat to supercharge his spellcasting, and pump the melee? Some extra actions would be nice so if you don't care about the dual progression crap, RKV could be nice. Alternatively, stat stack as Dragon stats tend to be high.

Dual progression of spells is banned for being stupid in the forst place, but manoeuvres and spells is allowed.
But what is Cleric of Tiamat? Google was uncharacteristically unhelpful.
Also, stat stack?

Making him a dread Necromancer on the other side of his dragon levels could be very useful and let him have an entire army to back him up.

You don't need class levels to have minions though.

I'd go with a adult, Xorvintaal (MM V, template) Black Dragon, with Twist of Fate ability, and then the Rejuvenation ability(Makes him make a chance of being a recurring Lillian as well(adds +1 CR for a second ability, don't add or pick something else if he is a one shot boss). Have the other half of the gestalt be factotum.

Ohhh, very nice, very nice. But making his other half factotum I'm not so sure about, I'd really like him to have some casting (beyond Dilettante), so if he loses his dragon casting I'd really like his class levels to make up for it somehow.

[Eldariel]

Dual progression of spells is banned for being stupid in the forst place, but manoeuvres and spells is allowed.
But what is Cleric of Tiamat? Google was uncharacteristically unhelpful.
Also, stat stack?

Tiamat is the deity of evil dragons. The Dragon being her Cleric is...sorta obvious. As for stat stack, you could add various levels and feats in accordance to X Stat to Y bonus, as Dragon stats tend to be quite high across the board and as such, gain great benefits from applying various stats to various things, like AC, to hit, damage, etc.

[Myou]

Tiamat is the deity of evil dragons. The Dragon being her Cleric is...sorta obvious. As for stat stack, you could add various levels and feats in accordance to X Stat to Y bonus, as Dragon stats tend to be quite high across the board and as such, gain great benefits from applying various stats to various things, like AC, to hit, damage, etc.

Oh, you just mean make him a cleric? XD
I thought it was a feat or something.

[Machiavellian]

I actually like the combo of the Templated Dragon and the Cleric, but with this add-on:

1. Use Dragons of Eberron to find either Loredrake or the one that turns your spellcasting from Sorcerer to Cleric. This will beastify your spellcasting

2. Take Unholy Ravager of Tiamat (Draconomicon) as the other side of the gestalt. LOTS of fluff and crunch.

3. Possibly, make him a reusable villain, by having the PCs face him again, though now a Dracolich on top of everything else!

[gbprime]

Why over complicate?

Make him a rogue. Use a minion or a spell to flank a PC, then add all that lovely sneak attack bonus to the dragon's HTH attacks. Add a level of shadow dancer on top of that if you like to make the dragon capable of just disappearing on them, then Arcane Trickster to up both sneak attack and sorcerer levels.