Bushiroad will release That Time I Got Reincarnated as a Slime Vol. 3, a booster set for Weiss Schwarz TCG, into retail on July 21, 2023.

The new booster set is compatible with the previous Slime booster sets and may be used with cards beginning with the number [TSK/] (see "'The Time I Got Reincarnated as a Slime' Comes to 'Weiss Schwarz'"). The set features hot-stamped sign cards of Miho Okasaki (Rimuru), Tomoaki Maeno (Veldora), Makoto Furukawa (Benimaru), Sayaka Senbongi (Shuna). MAO (Shion), Rina Hidaka (Milim), Atsumi Tanezaki (Mjurran), and of Taiki Kawakami, the mangaka of That Time I Got Reincarnated as a Slime. There are 100 total types of cards plus 50 types of parallels in this set.

The release of this set will also feature a Tournament Store Assist PR Pack campaign for retailers. It allows stores to give away a special Tournament Store Assist PR Pack per booster display of Slime Vol.1, Vol.2, or Vol.2 purchased, while supplies last. Each pack contains one random type of 5 foil PR cards.