Hey dzdt, will it matter which REU? In other words, would the 128K version be enough for this to be supported or would it need more RAM (e.g. 512kb, etc.)?
The DMA capabilities are present on all versions of REU. Somewhere MrSid said this Sonic game requires 256k of REU; I would assume that is mostly used for level data and extras; 128k should be plenty to handle the unpacked data for scrolling around a single level.