Hey fellow Diablo player! When it comes to defeating bosses in the campaign, it’s essential to understand their mechanics. Make sure to have the right balance of offense and defense in your gear. Utilize crowd control skills to manage minions while focusing on the boss. For optimization, prioritize gear with stats that complement your build. Look out for set bonuses for extra boosts. Efficient leveling involves running Rifts and Greater Rifts for experience and loot. Don’t forget to adjust the difficulty to find the right balance between speed and challenge. Good luck on your campaign journey!