Mercy uses a 6-round Feistel network structure with partial key whitening. The round function uses a key-dependent state machine which borrows some structure from the stream cipher WAKE, with key-dependent S-boxes based on the Nyberg S-boxes also used in AES.
Mercy employs a 6-round Feistel network with partial key whitening. Each round includes a state machine that mirrors the design of the stream cipher WAKE and utilizes key-dependent S-boxes similar to those used in AES, based on Nyberg's S-boxes.