Using 3 participants in the command can now create a double battle and using 2 participants can create a double battle if one participant is an NPC set to double battles.
We are enforcing the use of this version for clients, as it fixes an issue outlined in this Mojang blog post
#Minecraft 1.8.8 cracked servers update
In this update refreshing external files will reflect minor changes to Pokémon stat files. and is required for a Pixelmon client to run. The minimum Forge version for this update is 14.