What seems to be Japanese packaging for Red Dead Redemption 2 has appeared online and, if genuine, it shows that the PS4 physical edition is spread across 2 discs.
On the game’s back cover, a symbol indicating the double-disc format is shown:
『レッド・デッド・リデンプション2』ディスク2枚組が確定。PS4版ダミージャケットより判明 – https://t.co/U0eZRV0zOp pic.twitter.com/H2BxnMXP2Z
— ゲームのはなし (@gamenohanashi) October 17, 2018
Double-disc games are more familiar from older generations of console, when games could far outstrip the storage capacity of optical discs.
Source: IGN.com Red Dead Redemption 2: Physical Edition Could Come on 2 Discs