No actual %, but some detail on where the styles more commonly drop from, and whether you will only receive for 1st or 2nd placement, or in the case of Battleground Runner, equal for win/lose.
Hopefully someone has a more complete answer as I'd like to know this myself.
That said, you'll tend to get the armor pages first, then weapons
Also, the Horned Dragon and Fanged Worm, only drop from the Battlemaster's coffer (for doing the purple daily)
Stormlord is from Flag Games (Capture the Relic & Chaosball) with better chance if you win
Battleground Runner is from Flag games, with equal chance 1st/2nd/3rd
Firedrake is from Land Grab (Domination and Crazy King), with better chance if you win
Pit Daemon is from Deathmatch, with better chance if you win
The drop rate will go down as you get more and more of them, since you get a random page, and if it's a duplicate, you just won't see it at all, since they're bound style pages and you can only learn them once.
The drop rates, particularly on Fanged Worm and Horned Dragon are abysmal. I have a total of 22 out of 64 pages (interestingly enough I have every single waist piece). During things like MYM and anniversary event, I often do the daily on more than one character. 4 so far today alone and not a single page. It's honestly terrible, particularly the reverse reward structure with the more you get the less likely you are to get one.
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