A psion spending points to manifest the equivalent of a ninth level spell is not going nova, that's business as usual. Going nova is a psion throwing 4+ powers of their highest capacity at the same time.
It should be noted that putting all of your eggs in one basket OUGHT to result in overwhelming effects. You wouldn't do it if it didn't. Said psion doesn't have the capacity to do that twice (at least, not twice in one day), and if circumstances are ever so dire to actually warrant such action then it had better solve the problem. It's
not an efficient use of power points. It's a desperation move.
I mean, in 3.0 (this was nerfed in 3.5), a sorcerer/incantatrix with the right feat loadout could do this:
Turn 1:
- Swift action: Quickened Haste
- Haste action: Time Stop
- Standard action: Maximized Delayed Blast Fireball (5 turns delay)
Turn 2:
- Standard action: Maximized Delayed Blast Fireball (4 turns delay)
- Haste action: Maximized Delayed Blast Fireball (4 turns delay)
Turn 3:
- Standard action: Maximized Delayed Blast Fireball (3 turns delay)
- Haste action: Maximized Delayed Blast Fireball (3 turns delay)
Turn 4:
- Standard action: Maximized Delayed Blast Fireball (2 turns delay)
- Haste action: Maximized Delayed Blast Fireball (2 turns delay)
Turn 5:
- Standard action: Empowered Delayed Blast Fireball (1 turn delay)
- Haste action: Empowered Delayed Blast Fireball (1 turn delay)
Turn 6:
- Standard action: Empowered Delayed Blast Fireball (delay to end of turn)
- Haste action: Empowered Delayed Blast Fireball (delay to end of turn)
- Swift action: Quickened Dimension Door (GTFO)
- Time stop expires. 120d6+840 (average 1260) fire damage worth of Delayed Blast Fireballs simultaneously detonate. Reflex save (DC 32) up to 11 times for down to half damage. Fortitude save (DC 15) between 7 and 11 times (depending on how the damage dice rolled and if you made the last four reflex saves) or die instantly. If target resists fire, use the Energy Substitution feat to make it all sonic damage instead.
Yes, there ARE 10th-level spells in there. Incantatrices can do that. Yes, the sorcerer is out of 9th level spells after this, and mostly out of 8th level spells. And importantly: yes, there are better things the sorcerer could do with those spell slots if she doesn't
have to deal this much damage in a single round.
No, no, what I'm actually afraid of is the ranger that was in my party in a campaign I played back in college. I don't know
what the heck kind of ability he found in an official splatbook that let him use Perform (Dance) checks to allow a single attack roll to apply to all melee attacks he made that turn, but he was dual-wielding +5 keen shocking burst scimitars. That meant on a roll of 15 or better, he could unload up to eight 3d6+1d10+24 attacks
per round and never worry about running out of resources.