anchor.diff:          | Update
           | UpdateAvatar of Avatar
           | UpdateFieldTransition
  -        | UpdatePropState of int * Prop
  +        | UpdatePropState of Prop
           | MenuTeamOpen
           | MenuTeamAlly of int
           | MenuItemOpen
  
positive.code:                  Content.entities field (fun field _ -> field.Props) (fun props _ -> props) $ fun _ prop _ ->
                      Content.entity<PropDispatcher> Gen.name
                          [Entity.Prop <== prop
                           Entity.Prop.ChangeEvent ==|> fun evt -> let prop = evt.Data.Value :?> Prop in msg (UpdatePropState (prop.PropId, prop))]
  
                   // spirit orb
                   Content.entityIf field (fun field _ -> Field.hasEncounters field) $ fun field _ ->
  
negative.code:                 // no transition
                  | None -> just field
  
              | UpdatePropState prop ->
                  let field = Field.updateProp (constant prop) prop.PropId field
                  just field
  
              | MenuTeamOpen ->
  