Castle & Dragon

Castle & Dragon (城とドラゴン) is a strategy game from Asobism's Dragon series released for iOS and Android in Japan.

A Rockman collaboration with the game was announced on February 10, 2018. From February 16 to March 2, Rockman could be obtained as a playable character. His default attack is the Rock Buster, and his special skill is Rush Coil. Players could also obtain costumes and weapons to change his appearance and default attack. Swordsmen (the base units from the game) could also be dressed like Rockman and Metalls, the costumes being obtained in event stages to square off against Dr. Wily's robots. Wily would also invade the player's castle with the Wily Machine 2.

The Rockman event returned in 2021 between March 12-25 with additional content, a Roll costume for Rockman and a Dr. Wily costume for swordsmen, and a promotion was made in the game's official Twitter, with five winners obtaining a copy of R20+5 Rockman & Rockman X Official Complete Works.

Rockman
Rockman is obtained by buying his egg in the shop, which is shaped like a 1UP. It is available in two versions, one bought with CP (containing only the egg) and other with paid rubies (real money, also including his pixelated costume and bonuses).

Event stages
Players can try any stage for free up to three times per day. Further attempts in the same day requires Rubies.