Note: the devs lied about them all being inside the game.

K2-main page rotating banner

is the T5 in the ultimate level quest title part of the code?

T3 -- On Frozen Chocolate Gacha info description.
This one is not even hidden it's literally in writing next to "Frozen Chocolate!" , so it's different from the rest of the ones listed here.
The picture was posted on the Weekly Gacha thread but don't think anyone noticed it.

w11 on the current mission banner in the events tab beneath the game.

As much as I am happy you guys are sharing letters. You guys are aware of the caveats of this contest right?

I've found 14

k15 r12 o4 b1 p7 s8

K15 special tab event banner
S8 album event
R12 limited event gacha
B1 event info page top
P7 event info page bottom
O4-at the banner when you choose quest

thats actually only 6 out of 16 characters

they failed to mention this specifically in the news post.

Also, 1000 rainbow crystals for the upcoming rarity growth update would've been a much better reward than a regular rainbow ticket, however this is being too optimistic that this game will last until the end of this year.

how does this work? could only one guy get it?