SSMB member Paraxade managed to extract a bunch of information from the new Rise of Lyric patch and was able to post a bunch of previously unnoticed changes including some information which explains why the patch is so large as well as provide a video showing before and after patch.
The details are as follows.
- The cutscene where Lyric takes control of Metal Sonic has been updated with different lighting effects. Strangely enough this is the only updated cutscene.
- The controller diagrams in the pause menu have been updated with some slightly different colouration; for instance, blue rings around the home menu.
- Six levels have changes to them: Cliff’s Excavation Site, Bygone Island, Tomb of Lyric, Lyric’s Weapons Factory (past), Crater Lake, and the Ocean Purification Plant. FWIW, each level is stored in a single massive .stream file, which means any changes to the level necessitates including an entire new .stream file for that level in the patch data. The new .streams for these six levels adds up to over 1GB; that’s why the patch is so big. I don’t know specifically what they changed in those levels.
- New executable file; this is where all the hardcoded bugfixes are.
Now if you don’t spot the problem. This is why the Sonic Boom patch is so big and it also highlights just how bad the game is on a technical level.
Here’s the explanation. Collisions and other data are stored in a giant stream files meaning if you make 1 change to the entire level, your patch has to include ALL data from that original file including the changes.
For instance, say you had a stream file which was 200MB. And you wanted to add 1 ring to that stage. Your patch would be 200MB + the data for that one ring.
The changes are not that big, but due to the way the game is programmed, entire files which do not have any changes in them have to be included in the patch or else the patch will fail.
This means that any future patch is likely to be massive, even if all it did was make one single change to a stage.
As well as the details he also provided a video showing how different one cutscene now looks. (See above)
Source: Sonic Stadium Message Board