Chapter 3: the first weird battle

I spawned at the 5th gym. Which was weird because I saw on the menu that it had no badges. I walked outside and i was immediately taken to a wild pokémon battle. I saw missingno. "A wild missingno appeared!" "go, eevee!" I was suprised. I selected pokémon and pressed A. I saw eevee, serperior, pidove, deerling, reshiram and pidgey. I was suprised it had reshiram in the team because it had no badges and it spawned at the fifth gym. I pressed B and pressed A on fight. It had tackle, shadow ball, swift and bite. I selected bite and pressed A. "Eevee used bite". "A Critical hit!". "Missingno used Shadow claw". I saw the HP bar was low so i selected items, pokéballs and then I saw it had 99 master Balls. I pressed A twice and I caught missingno. I started to believe there was an unknown glitch in this game.