Plot ideas for a birthday party

Hello! I apologize in advance if this is the wrong sub for this.

My kid is turning 6 and he is \*obsessed\* with transformers. We have a little trail through the woods next to our house. I thought that, for his birthday party, he and his buddies could be Autobots and go on an Energon (blue gems or rocks or something idk yet) hunt in the woods. Some adults (the fun aunts n uncles) would be Decepticons and jump out to stop them from getting the Energon. Water guns will be involved bc it’ll be a summer birthday. The kids will have masks (thank you AI + Staples printing + some elastic) and I might fashion some cardboard “costumes” for the Decepticons (like Starscreams wings).

1. Do I even need to bother with a plot?

2. If so, what would it be? Starscream tries to stop them, gets defeated, and then they move on to Megatron? What other Decepticons could I involve? My son has opinions about their special abilities (like Soundwave) and I’d like to make it more interesting than just “walk along and spray adults with water guns” though that actually might be fine?

Thanks friends