Trade Secrets

This will notably increase your XXX, though not past the level cap.

What is that level cap?

200 for every stat.

Edit: And while we’re here, the best use for Trade Secrets is the Searing Enigma and five Antique Mysteries.
edited by Cocytus on 9/30/2014

thanks.

but should i get the items even in early game? 150 cp are quite a bunch. also, should i keep the enigma or sell it for money?

The enigmas aren’t really good for much, even in the endgame. You can use them to grind for like, impossible theorems, but that’s not really useful. Sell it, unless you feel like hoarding.
As for grinding, there’s a much better way to do it. Farm second chances through social actions, then burn five of them for stats. It’s much more efficient, and doesn’t use nearly as many actions.

If you are interested in a room at the Royal bethlehem you’ll probably find the Antique Mysteries to be pretty useful since you’ll need a bunch of them. (I mean it’d still take almost a year to get it using Trade Secrets but)

Searing Enigmas i mostly just sell (they are really valuable) although maybe i should start saving for an Impossible Theorem.

In my opinion, you should avoid selling anything that you cannot easily replace. It is better to hoard resources because in the event you do need the money it would be no trouble to just sell it then. But in the event you suddenly needed Trade Secrets then you will be grateful that you held off on selling them.

On the other hand, if you really want Primordial Hints you would’ve benefited from trading in your Trade Secrets before they changed that part of the reward to 5 x Antique Mysteries, of which you apparently need seven to get a Primordial Hint. Hard to say for sure what to do sometimes.

There is one tiny caveat to that, though: you can’t be sure that Trade Secrets will always be capable of being traded in for the same reward. For example, it used to be one Enigma and one Hint - now it’s one Enigma and 5 Mysteries. Same Echo value, but who’s to say that won’t change…?

Personally I’d rather have the mysteries 'cause I need that Royal Beth room :P

But also trade secrets are the only way to get classic short stories at this point I believe.

I believe they changed the reward from Hints to Mysteries because the latter was more useful. There are very few things that require a Primordial Hint.

Makes sense, though not much requires mysteries either beyond the Royal Bethlehem room.

Is it possible to stockpile Trade Secrets? Or do you only get one if you’ve used up your last one?

You can stockpile them! I’ve got 24 of them on my main.