[Update] Dark Souls 2: Seamless Co-op - More game engine changes

Hi everyone

Happy new year! I hope you have all had a nice holiday period, and that your 2026 has got off to a good start!

I have been taking some time away to spend time with family overseas, but now I'm back to working on Dark Souls II. I've also been working on releasing a hot-fix for Blue Acolyte to patch a highly exploitable server-based exploit - I will discuss this more in a free-to-access post.

(more) Engine changes

As the thumbnail of the post shows, the length of the player name is uncapped in the seamless co-op mod (up to 32 characters) rather than the 14 characters it was previously capped at.

Some players could already get around this by using Steam big picture mode and using the on-screen keyboard with their controller. This works because when you press "OK" after inputting your name on the Steam overlay it passes the entire name string as a single character.

As of this change, you can just type as normal with your keyboard.

(more) Event flag updates

Something that has been a challenge in Dark Souls II is getting event flags to work correctly. As I've mentioned before, in the other games all event flags are accessible and readable at all times, for any map.

In Dark Souls II however, the 'EVENT_AREA_MAP_LOAD_COUNT' is equal to 3. The engine is hard-capped at having a maximum of 3 different areas loaded at the same time and increasing it is proving to be incredibly difficult.

The issue is that I would need to increase the size of 'remote_area_event_flag_buffer' to 'DS2SC_GLOBAL_MAP_COUNT' (42) similar to the 'local_area_event_flag_buffer' as it can only hold 3 areas in it at once (intended for just online play in 1 map).

That involves increasing the array size, which is fairly simple, but then moving every single reference to offsets distal to the expanded inline array. To do this I've had to re-write a large part of the EventFlagBuffer class, and parts of the DLMemoryInputStream involved in writing updated event flags to your save file.

Overall release progress

People are understandably anxious for a release of the mod and have been asking for early-release copies.

As of right now, the mod is functional (I've almost finished 3 separate playthroughs with different people) but there are significant issues for non-host players such as:

Not receiving souls from bosses if you have fallen and are in spectate mode

Flag-dependent enemies (e.g. bosses, drakes) respawning on bonfire rest

Unsynced NPC dialogue

Getting stuck at bonfires when someone rests as you are warping

No PvP / Invasion implementation

Incomplete reversing work on the expanded map limit

I am currently not happy for people to play the mod in this state - especially since people tend to expect a lot from me - but it is shaping up really nicely. It's hard to give an ETA right now as there is still a few unknowns. Taking a guess though I'd say I'm in the final stretch of development and once the issues above are solved I will have an early build ready to test.

As always - thank you for your patience and a huge thank you to all of my supporters <3

Take care,

Yui