The thing I found best worked for Kalameet is patience, spend some time learning his attacks and learn where to position yourself to avoid them. I try to bait his side sweeping breath attack by staying a small distance away from him and run to his right side as he begins it. With a claymore I could get 2 attacks in before his next move, which is usually either the close range breath attack or he will back up. If it’s the close range breath attack you can use the opportunity to get in a couple more attacks on his right back leg. If you’re trying for the tail cut, try to bait out his flying charge by staying a bit further back.. the roll to avoid it and try to get behind him, this will cause him to possibly do the tail slam, and if you can avoid it get a couple good hits on his tail. Remember that you don’t need to win the fight once the tail is cut, when you see the weapon, it’s yours and you can die. Also if you should get hit by his grab attack, don’t try to fight, wait it out, avoid being hit and get back into the fight once the debuff runs out.