How do you make a sonic chao on sonic adventure 2 battle

Well if your like me, reading on several different websites about giving him green drives and he will eventually turn blue, then you go back to your game and keep on giving him drives till he's level 99 and still nothing? Well here's your solution. Give him green chao drives till level 16 in running. By the way make him neutral by taking care of him with both sonic and shadow. Then give fruit till he's level 16 in stamina. Even when he rejects the food, keep giving it to him. When he is level 16 on both running and stamina he should automatically evolve. If he doesn't evolve at level 16 keep going and he should evolve very soon. Hope i helped!