The Vorpal Tribble said:
This feat lets you gain 1 power, after you...
One power? Unless you are talking about your revised version, perhaps. But if it only gives you one power, I'll take Expanded Knowledge any day. If it gives you the potential for more than one power, then you should say
"1 power for each time after you ..."
The Vorpal Tribble said:
#1. Find a psionic opponent.
May or may not be difficult. This is totally campaign dependant. In general, I typically find it bad mechanics design to have balance rest in something campaign (or DM) dependant. In my games, this is not the rare occurance you propose that it is. In my games, meeting a psionic character is just as common (if not moreso) than meeting a sorcerer.
The Vorpal Tribble said:
Not typically difficult for a party who is determined. Sure, they can run. But in any given CR equivalent encounter, the party should be able to prepare for a character to run and hunt them down and kill them if desired. This has no relevant part in balance.
The Vorpal Tribble said:
This likewise has no relevant part of a balanc discussion. Assuming that we've gotten to #3 assumes that the creature is dead. Butchering it doesn't even require any kind of rolls! You just do it. It happens. No part of balance can be found in this step.
The Vorpal Tribble said:
#4. Make a very high skill check.
And, if a character is going to take this feat then they will likely find it useful to make sure they have access to several +10 shards. So, that very high skill check is now only average at best. Sure, a +10 shard is 1,000 gold. But seriously, who wouldn't pay 1,000 gold in this circumstance to gain a new power? And, if we're going to talk about averages we could say that the laws of averages say that for every 2,000 gold spent on shards they should get 1 power. You tell me that 2,000 golld per power isn't a good deal for a wilder or psion!
Just to do the numbers ... the DC set in the OP is 25+power level. So ... let's take this at the basic level of 9th. Assuming that a psion has a modest opening attribute (16), a modest ability enhancing item considering INT is their main casting stat (+4), and they've used their 4th and 8th levels to add to their INT score. None of those are absurd assumptions. That means that the character's INT sits at 22, giving them a +6 modifier. Now, being 9th level they have 12 ranks in psicraft. So, they have a psicraft check of 18 (or higher, because I didn't go for a maximum argument of numebrs here.) The DC for the 5th level power is 25+5 = 30. So, they need to roll a 12 on a d20 to make it. But, throw in a mere 1,000 gold piece +10 shard and they need to roll a 2. If they had any kind of INT buff up, if they were able to be aided by another, started with an 18 instead of a 16, or somehow else able to get a mere 2 more points to their mod, this "very high skill check" is actually a gimmie. You technically wouldn't even have to roll, unless your DM is strict about a natural 1 being an auto-fail for skill checks as well - and not all DMs are. This very high skill check is easily made to not even matter. There is little balancing factor in this part!
The Vorpal Tribble said:
And you still don't get to have any power you like. You gotta choose from whatever this guy had, which doesn't require it being something you want.
This has a bit of balance to it. However, the character still gets one. They become more versatile. It may not be on their top 3 list, but it is still power.
The Vorpal Tribble said:
This requires much more effort for a higher reward, assuming you find more than one psionic creature.
Again, your concept of balance is so campaign dependant. I like what the above poster had to say about keeping it for your game. You want it in your game, then add it! But if we are going to talk about good feat design from a mechanics perspective which looks at the broad spectrum of game scenarios ... then balancing factors which are campaign specific are just poor design. A psionic character in one of my campaigns could likely use this power an average of 4 to 5 times per level. I love psionics that much, and use them as often as wizards and sorcerers. All of your comments about "if you find one" fall completely flat in games like mine. When designing a feat, you have to take all tables into account - not just your own.
Balance with mechanics, not campaign design. That will get you more positive feedback. As it stands, as per your request, I have gone through your balancing factors and demonstrated that there is little balance from a mechanics perspective. No way would this feat be allowed in my game.
One power for each time this feat is taken - and that power can be swapped with each new psionic encounter that qualifies - now that's balanced mechanically. No longer is the campaign specific quality of "how often psionic encounters happen" in the balancing part. Now, the balance is established by the limit of powers gleaned. It is more flexible than Expanded Knowledge, but there is more investment involved as well.