[4e] Flying Elven Death Squad

[Edea]

Dispel Magic pops the CC, because it's a Conjuration.

Not a single monster in the MM has Dispel Magic. Not a one. You'll have to make a custom monster specifically to pop it (which, of course, indicates that there's a problem, here). Worse, Dispel Magic requires an attack roll and has an Attack entry; thus, it is an attack, and since the Cloud Chariot cannot be attacked, I'm pretty sure it's immune to Dispel Magic anyway.

I don't see any rules for how to control the horse/chariot - I would rule that the cloudhorse acts as a Mount, so someone has to ride the cloudhorse to direct the whole thing. It doesn't actually explicitly state that the horse and chariot are under your control at all, only that it has Fly 8. Sounds like it needs errata.

One of the characters takes the Mounted Combat feat. Done. Actually, they should ALL probably have it eariler anyway, so they can start riding around on more mundane flying mounts before Level 22. It's not like you have to make a Ride check anymore to stay on your mount, and it uses your Stealth checks to hide, not its own.

Also, the character who conjured the CC has to remain within two squares of it at all times, or it goes away.

Why would you ever want to leave it? Everlasting Provisions and a Handy Havesack. That's why these elves are so obese, they never get out of the freakin' car!

One more thing: this really leaves the party at mercy of things that fly and have Blast attacks. What flies and has Blast attacks? I think you are crunchy and taste good with ketchup...

We already talked about the use of Stealth while riding it, because the chariot grants cover. Even dragons have -TERRIBLE- Perception for their level versus Stealth builds. That means a very, very large percentage of the time, the dragon/flying whatever doesn't know you're in there (YOU do, but the beast does not), and breath attacks, Area or not, still require an attack roll, meaning it's an attack, which means they can't target the chariot with one. It literally can't do anything to the chariot or its occupants until it beats an opposed Stealth check. Given that a lot of these guys were planned to be Deadly Tricksters? Not happening anytime soon. Once again, you'll have to customize a monster specifically to beat it. That's a Bad Thing (TM). As for the rider, there are plently of ways to activate concealment or cover on him if it's necessary (honestly they probably just switch around if one gets hit).

On top of that, breath weapons are a measly Blast 5; we're talking up to -40 feet- away from them. Even with a speed of 12 versus 8, that's 10 turns before the dragon catches up, and 8 turns before they're in blasting range, and that's assuming they don't get Slowed or Stunned first.

EDIT: In fact, even the Tarrasque is in trouble. Just take Far Shot and Distant Shot; your range is now 45 squares without penalty, meaning you're able to attack him outside of his gravity aura.