I'd be ok with switching adapt body, ectoplasmic form, immovability, and psionic dominate to 3/day. Actually, adapt body lasts for 12 hours at a time, so we could cut it back to 1/day.
So if we put those all together you're talking...
at will -- claws of the vampire, control body, create sound, inertial barrier, read thoughts, telekinetic force, telekinetic maneuver, telekinetic thrust
3/day -- ectoplasmic form, immovability, psionic dominate
1/day -- adapt body, suspend life
...plus it's current PLAs of...
At-Will—
greater concealing amorpha,
detect hostile intent,
detect psionics,
personal mind blank,
psychic vampire; 3/day—
catapsi,
psionic dominate; 1/day—
psionic blast,
ultrablast.
To make:
Psi-Like Abilities (Ps): At-Will—
claws of the vampire,
greater concealing amorpha,
control body,
create sound,
detect hostile intent,
detect psionics,
inertial barrier,
personal mind blank,
psychic vampire,
read thoughts,
telekinetic force,
telekinetic maneuver,
telekinetic thrust; 3/day—
catapsi,
ectoplasmic form,
immovability,
psionic dominate; 1/day—
adapt body,
psionic blast,
suspend life,
ultrablast. These abilities are as the powers manifested by a 12th-level psion. The save DCs are Charisma-based.
Well, we could just copy from the power. Something like this?
Adapt Body (Sp): Once per day as a standard action, a master scorpion can adapt to hostile environments for a 12 hour period. The master scorpion can breathe and move (though penalties to movement and attacks, if any for a particular environment, remain) and takes no damage simply from being in the environment, surviving as a creature native to the environment. The master scorpion can adapt to underwater, extremely hot, extremely cold, or airless environments. Any environmental feature that normally directly deals 1 or more dice of damage per round deals half damage. Once this ability is active, the master scorpion instantly to any environment it enters.
That approach works for me, although I'd make a few tweaks to the text.
If we make it a separate SLA we'd better remove
adapt body from its PLA list:
Psi-Like Abilities (Ps): At-Will—
claws of the vampire,
greater concealing amorpha,
control body,
create sound,
detect hostile intent,
detect psionics,
inertial barrier,
personal mind blank,
psychic vampire,
read thoughts,
telekinetic force,
telekinetic maneuver,
telekinetic thrust; 3/day—
catapsi,
ectoplasmic form,
immovability,
psionic dominate; 1/day—
psionic blast,
suspend life,
ultrablast. These abilities are as the powers manifested by a 12th-level psion. The save DCs are Charisma-based.
Hmm... upon reflection I'd rather make it 3 times per day. That way it'll get round-the-clock environmental protection, rather than having to choose between baking in the desert sun or freezing in the desert night.
Actually, I'm also wondering whether we should slightly rephrase the name so it's not identical to the psionic power. e.g.:
Body Adaptation (Sp): Three times per day, as a standard action, a master scorpion can adapt to hostile environments for a 12 hour period. Once this ability is active, the master scorpion instantly adapts to any environment it enters. The master scorpion can breathe and move and takes no damage simply from being in the environment, surviving as if it were native to that environment (though penalties to movement and attacks, if any for a particular environment, remain). The master scorpion can adapt to underwater, extremely hot, extremely cold, or airless environments. Any environmental feature that directly deals 1 or more dice of damage per round deals half damage to the master scorpion.
This ability can be dispelled and is the equivalent of a 5th-level spell with a caster level equal to the scorpion's Hit Dice. A master scorpion can dismiss an active
body adaptation or create a new
body adaptation effect as a standard action.
Another alternative is to make it At-Will:
Body Adaptation (Sp): As a standard action, a master scorpion can adapt to hostile environments for a 12 hour period.