Does the Timeless Body power protect you from Fission's damage? And therefore allow free Reality Revisions?

Question

So this is how I understand the Fission power.

1. The definition of "damage" in this power's description includes "xp damage." Something about "ability drain" setting precedent that "drain" is a form of damage, therefore "Energy Drain" is damage, therefore level loss is "damage", therefore xp loss is "damage". Hence "xp damage."

2. If the Fission is alive when the duration expires, you rejoin with it and take half of the "xp damage" the Fission took.

3. If the Fission is dead when the duration expires, no rejoining occurs and you take full "xp damage".

This is Timeless Body's entire ability description

Your body ignores all harmful (and helpful) effects, beginning when you finish manifesting this power and ending at the end of your next turn. While timeless body is in effect, you are invulnerable to all attacks and powers.

So does this work?

1. Manifest Fission.
2. Have the Fission deplete its XP supply via Reality Revision
3. Right before the Fission duration expires, manifest double extended Timeless Body by expending 2 psionic foci to apply Extend Power twice. That's 4 rounds of invulnerability.
4. Fission duration lapses, causing you to rejoin with your duplicate. But because you are invulnerable and ignoring all helpful and harmful effects, you take literally 0 damage from the rejoining.

And that's it. Infinite free Reality Revisions.

On that note, does this also work?

1. Manifest Fission
2. Right before the Fission duration expires, you manifest double extended Timeless Body on yourself.
3. Right before the Fission duration expires, your duplicate manifests dissipating touch linked to psionic revivify and touches himself. The result is the dissipating touch kills him.
4. After Fission duration lapses, you take 0 "xp damage" from the 200xp cost it took for your duplicate to manifest psionic revivify because you are both invulnerable to powers and ignoring all harmful effects. Also your Fission duplicate is revived thanks to the linked Psionic Revivify. End result is now you have an "instantaneous" duration Fission duplicate.
5. Have the Fission duplicate expend all of his XP on reality revision.
6. Manifest Assimilate on your Fission Duplicate to "kill" him. Your Fission duplicate won't do anything you won't do and since you won't kill yourself or let yourself be killed, the duplicate will do the same. So instead you assimilate him back into you. There should be no objections here.

Answer 1

Paying experience is not damage.

Frame challenge:

The definition of "damage" in this power's description includes "xp damage." Something about "ability drain" setting precedent that "drain" is a form of damage, therefore "Energy Drain" is damage, therefore level loss is "damage", therefore xp loss is "damage". Hence "xp damage."

The argument here boils down to:

1. Ability drain is a form of damage.
2. Therefore all forms of drain are damage.
3. Therefore energy drain is a form of damage.
4. Therefore paying an experience cost is a form of damage.

The first argument: Fission lists ability drain in the "all damage" section, and the ability drain section offhandedly refers to it as damage.

The second argument is where things fall apart: ability drain counting as damage does not mean all forms of drain are damage. This is a faulty generalization fallacy (or, more specifically, an association fallacy) unless there's a specific rule that states "all forms of drain are damage."

The third argument has a problem: "energy drain" and "negative levels" are not the same thing. Negative levels are sometimes referred to as "drain," but they are not synonymous: see Are negative levels necessarily energy drain?

The fourth argument doesn't seem to have any basis in the rules, as far as I can tell. You cannot lose a level from paying experience and as there is no functional difference between being level 15.0 and level 15.99, it's extremely tenuous to claim that voluntarily spending part of a level is "energy drain" and therefore "damage."

Overall, I do not think arguments 2, 3, or 4 hold water...but that gets us to the same destination. Paying an experience cost not counting as "damage" means that Fission just flat-out ignores it.

Fission, as written, just lets you dodge the exp cost.

Fission is a poorly-written psionic power, but there's a list of what happens when you rejoin:

When the duration expires or when you dismiss the power, you and your duplicate rejoin, no matter how far from each other you are. You gain back any power points the duplicate has not spent. At the time of rejoining, you take half of the damage your duplicate has taken since this power was manifested. This damage could potentially leave you with negative hit points, but it can’t reduce your hit points to less than -9. [...] All powers affecting a fissioned creature, either the original or the duplicate, end when the fission ends. All damage, including hit point damage, ability damage, ability drain, and ability burn damage, is added together.

As I do not agree that paying an experience cost is "experience damage," nothing in Fission would result in lost experience transferring to the original when the duplicate expires. Quite a few other things do not transfer from the duplicate — curses, diseases, poisons, etc. — as they aren't mentioned, and experience costs, not being included, will not transfer either.

That said, if an experience cost were treated as damage, Timeless Body would prevent it, but it's even vaguer than Fission. It's so broad and without clarification that this is fairly clear: Timeless Body states that you ignore "all harmful (and helpful) effects," and Fission says "you take half of the damage" which certainly counts as a harmful effect. You similarly wouldn't benefit from "you gain back any power points [...]," as that's a helpful effect.