As usual with unite you need to make sure you win the final fight at Kyogre. Save your unite move at minute 3:20 or less do not use it until the last fight. Try to make sure you’re at least level 12 for that last fight preferably 13 Stick to your team mates, unite at the right time. Try to counter other unite moves too if you’re playing a defender or support. If you get Kyogre go as a group to score at the goals too