Since I had too much time I compiled a spreadsheet about how to use NetMessage.SendData in you mod.
Terraria Tmodloader NetMessage.SendData
NetMessage.SendData ID,Name,Description,uses networktext,number,number2,number3,number4,number5,number6,number7 1,ClientHello,sends modloader version name 2,Kick,kicks the remote client player,YES, kick reason 3,LoadPlayer,sends remote client player info 4,SyncPlayer,syncs the player,player index 5
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