[4.2.2] Opcodes

If anyone has any new opcodes for 4.2.2 or can find them, post them here.

we currently focus on movement related stuff, so speed change + ack opcodes are needed now.


Made a small dumper to gather as much SMSG / MSG as possible and associated known opcodes to the dump.


Dump of movement opcodes by LordJZ


the SPLINE opcodes are what used to be normal ones, and the MSG_MOVE ones in this dump are FORCED

out of curiosity, hasn’t the movement been always spline-based in wow? I assume only handlers and opcodes need adjusting and silverice’s implementation is fine as is now?

Those splines are not really related to this, i guess its just a name Blizzard gave to these opcodes

seems to me spline opcodes would be ones sent to the client all in one shot (like waypoints) and the others are sent to possibly interrupt splines or force a creature/npc to change it’s state in response to some other criteria, such as attack, or gossip. Which could explain why we have such a hard time getting movement working 100% correctly, using the wrong opcodes, and, until recently, sending the opcodes one at a time, instead of all in one packet…

The ones that end in ack are a response, letting the client tell the server that the opcode was received, which could possibly be a reason that the server and client get out of synch so often, if these are not being handled properly.

Not actually Paradox, its just a name, forced packets are sent only to the player who is getting the speed change, the spline ones are sent to everyone (even units) to notify nearby clients that the creature got a speed change.


forced = yourself

spline = everybody except yourself


made my day lol

New opcodes dump with JAM packets handlers. I had to code a small VM to get those, and I still have some problems with it, which is why some handlers are missing. It includes most (if not all) SMSG and MSG opcodes with handlers. I added the names of known opcodes (basing on WPP lists).