MyLoopStarter:
     type: world
     events:
         on server start:
         - run MyLoopScript
 
 MyLoopScript:
     type: task
     script:
     - foreach <server.list_online_players> {
       - if <def[value].equipment.boots.scriptname||null> == i@MyCustomBoots {
-        - cast speed duration:10s power:1
+        - cast speed duration:10s power:1 <def[value]>
         }
       }
     - run MyLoopScript delay:9s