If the player's don't know then they can open up the XPH, which one of the obviously has to have a psionic character.
It's basically like any other effect where the player is killed and no body is left.Also, if 100 is rolled and they fail the fortitude save I'd restrict how they can be resurrected and maybe make their be no way short of divine intervention. After all, being torn apart across the space-time continuum is pretty severe.
Basically you can go and test out theories, experiment, get information, what have you, but then no matter what you did it isn't permanent and no one is aware of it afterwords except you. Basically a case of 'if you could do anything without consequences...'I'm not sure about Split Stream's level. On the one hand it has both combat and non-combat applications so it should have a high level. And the descriptor of what it does certainly fits a high level power. On the other hand all of its uses appear very narrow.
It's 7th level because you can still be hurt and killed as normal.
Dimensional Anchor doesn't allow a save. This is just a higher-level, time-based version.Temporal Anchor: This power maybe should allow a will save? I'm not sure.