A new challenger has arrived in Onimusha Soul, Capcom’s browser based Onimusha game with cards representing characters from the entire series. Ryu shows up in a dream story as a fiend for players to fight. Your reward for defeating Ryu is a pair of zori (Japanese sandals) and he joins your group as a warlord.
Lilith and Morrigan from Darkstalkers made cameos in Onimusha Soul too.
Onimusha Soul was Capcom’s foray into the world of browser games, but so far Onimusha Soul is only for Japan.