This is an tool  for advanced modders. This Editor can  Deserialize and Serialize these Show Asset Jsfbs : Matchup, Nameplate , Superstar_Nameplate, Locator , Result, Replay , bg_universe. I Said this is for advanced modders at the beginning because to modify these files you still need to know what you are doing. 
This was something i have been working on quite sometime to make arena modding more streamlined.
Not all fields are identified as which is which but some of them are, if you find anything you can contact me i will update it.
If you are facing trouble deserializing any particular jsfb , please let me know (this application does have feature to save log so use it save errors)....