While it's still too soon for us to get more details about the next DLC batch for the only currently-active console Taiko title, everyone who is about to buy Dokodon! Mystery Adventure is eligible to be subject of yet another gift campaign!
Starting from tomorrow in every participating store, every purchase of the latest 3DS game will be paired with a B5-size note book and sticker sheet with many Taiko characters from the Wada family, together with a Taiko-labeled pen. If you want to nab these freebies for yourself, act fast before the supplies are over!
Source (Taiko 3DS 3 official website)