So... Celerity is not in the SpC, so kind of irrelevant to the thread, but I wanted to answer some questions people asked about my last post. See spoiler text.
akbearfoot: heh, my dervish didn't learn about empowered rays of enfeeblement until around L12, but after that he always carried potions of lesser restoration - worth every penny. He wasn't using belts of battle, because he needed the Str boost more (and we weren't using the MIC rules for combining them), but he could dance in, full attack and dance out without need for items, and was regularly doing 200+ damage/round starting at L11 (in one round at L15 he cracked 1000 damage, but that was an exceptional situation). He didn't actually get targeted that often, because the melee enemies couldn't full attack him, and if the opponents were mostly casters, they usually didn't realize how dangerous he was until after they were dead (or they wasted rounds trying to stop him with effects he was immune to). There were painful exceptions, though.
If you want to restrict belts of battle while allowing their use to help fighters get full attacks, maybe just houserule them to only the move-action option? Meleers really need a way to get full attacks (if they're not spirited charger types), to keep up with the rest of the party. It's never been a very big deal for me, but my meleers are a dervish and a pouncer, and in my recent high-level tables the consensus has been that if the meleers aren't getting to full attack every round, the casters aren't doing their jobs - so I tend to just assume meleers get full attacks, in balance discussions. If that's not the situation, I can see how meleers would feel weak.
Re wraithstrike: before it was banned in Living Greyhawk, people were talking about fighters taking three levels of wizard ONLY to get Wraithstrike. It also has the effect of making spellsword or arcane trickster builds
much stronger, and melee wizards (perhaps using a skilful weapon or Arcane Disciple: Divine Power to improve their BAB) can also become very dangerous. I have a problem with anything that gives fighters who dabble in magic, or full-caster wizards wielding swords, an immense advantage in melee damage over non-magical meleers. Also, it makes dragons just horrendously scary.
I agree the riders on the orb spells can be nice. My shadowcraft mage has actually started using shadow-conjured orb of fire now and then, because the rider is so pretty and her save DCs are quite high (and the party she's been playing in is very weak on direct damage). I still don't think the rider+damage makes them dangerously overpowered for L4 spells, though.
[sblock]My sorc only had Celerity for one game - she picked it up for her big finale, because I was absolutely certain it was going to get used against us (final two-round Living Greyhawk Core Special, with strong hints that we'd be facing the Greater Boneheart), and I wanted to have the option to use it myself

So yeah... I was actively abusing it, in that game, with Greater Arcane Fusion loops* and a cohort who could use Healing Lorecall to remove the daze (although I note I only resorted to the Greater Arcane Fusion silliness after the GM did it first). But after the game, I noticed just how many instances there had been where if I'd thought fast enough, I could've used Celerity WITHOUT the exploits and saved some resources (three exploding-enemy situations, another case where I used a one-time-only immediate-action Wish-like power to get an AMF when Celerity + AMF would've worked just as well, reactive counterspelling-with-damage against a certain nasty monster's spell-likes, readying an action and wasting that turn when I could have done what I wanted with Celerity...)
I suspect that even without the ability to remove/negate the daze, and without silly Greater Arcane Fusion nested actions, it's still a bit too low-level at 4th. Not sure if it's
broken if you remove the abusive combos, but it's very, very good.
StreamOfTheSky: using waves of enemies would help in some cases, but even so, if you weren't planning to use that move action next round, it's not like you've lost much. That said, giving up the ability to use immediate-action defences can be pretty important.
Btw, this only applies to the standard action version. I don't have a problem with the move- and full-round action versions.
How might one acquire daze immunity anyways? Barring one spell which is forgotten realms specific (and unique only to those who worship Ilmater), and an eberron dragonmark trait (something along that line), I can't recall any other ways of becoming immune to daze.
Even undead and constructs are not exempt (with caveats).
Favor of the Martyr in SpC might do it, although I'd be tempted to rule that "immune to any effect that will cause you to be dazed" = "immune to the entire effect of Celerity". Quick Recovery does it at the cost of a move action. Having someone cast Panacea or a Healing-Lorecall-boosted healing spell on you after the fact works as well - in the latter case, a low-level immediate-action spell like Close Wounds is good.
Flatus: in the example I was thinking of (and I suspect ElderBasilisk may have fought something similar), the sequence went like,
L19 enemy wizard (on init 49 - he had a succubus marshal on his team

):
-Swift action: activate Dispelling Cord (MIC)
-Standard action: chained Greater Dispel on PCs and their visible items. Dispel check is at +26 (+20 CL, +2 Dispelling Cord, +2 due to Spellcaster's Bane prebuff, +2 Elven Spell Lore feat). Takes 10 with Arcane Mastery, autodispels everything CL 25 and lower.
End turn.
-Immediate action: Celerity.
-Standard action: Sudden Extended Time Stop. Rolls max on duration. (This ALWAYS happens to me. I have never had a DM roll LESS than max on a bad guy's timestop duration.)
-Next 10 rounds: (dazed), Wall of Force (blocking escape route), Evard's Black Tentacles, Cloudkill, Freezing Fog, Maw of Chaos, Extended Lingering Flames, Cold-Substituted Extended Lingering Flames, Acid-Substituted Extended Lingering Flames, Electric-Substituted Extended Lingering Flames... and a bunch of others I don't remember. The lower-level spells were quickened. I did count up the spell levels at the time and there were over 100 on the battlefield by the time the timestop ended. The dispel had taken down our freedom of movement, heroes' feast and save buffs and shut off our resistance items.
Now, Celerity is not the only issue here

You could get nearly the same effect by using the standard action to greater dispel and the swift to activate a Belt of Battle and cast the Sudden Extended Timestop. Celerity specifically became more of an issue a round later, when one of us cast AMF and moved toward him, and he decided to teleport out as an immediate action rather than stay to be captured.
(The fight was more or less a tie - he got out with his succubus girlfriend, his familiar and a PC's body, we killed his other three lackeys and lost a PC and an animal companion. Given we were a L14 party and the fight was EL22, that's not bad, but still... ow, ow, ow.)
The final fight in the mod where my sorc had Celerity was very similar except there were three wizards, two epic, and they only had one melee lackey rather than four. The party was also L16, not L14. It went MUCH better. The top of the initiative order was a bad guy at init 70, who opened with pretty much exactly the same combo but with more L9 spells, but because we had Foresight active (from scrolls) and immediate-action defences such as Celerity, we were able to interrupt the nova. The fact that we had two PCs with inits in the 60s, so they didn't ALL get to go before us, also helped.
*For clarity, by "Greater Arcane Fusion loops" I mean:
-Cast Celerity, grants a standard action, and you will be dazed when that action ends
-Use that standard action to cast Greater Arcane Fusion, which you use to cast a L7 or lower spell of your choice, and Celerity, granting an extra standard action (still inside the first standard action)
-Repeat until you run out of Greater Arcane Fusions or decide to stop.
This is a way to pump out lots and lots of spells as a one-round nova, with very little your opponents can do to stop it - you're dazed at the end of it but that doesn't matter if they're dead. It's a bit like Timestop except you don't need L9 spells and you don't need to restrict yourself to lasting effects. I consider it an abuse of the rules and unquestionably broken, and I have pretty liberal standards for powergaming

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