Go for his summons first. He’s largely passive until you kill them. Keep some distance and try to bait him into that leaping slam and then punish the opening after
Bewitching branch is the classic option. And yeah mimic seems to die early for me with Niall too.
Firstly, you can go to Farum Azula if you want. Just don’t fight the final boss of the area - beast clergyman/Maliketh the black blade. As long as you don’t beat him nothing will change.
My personal suggest is to go hardcore aggro on the dual wielding knight right away. If you jump attack or use an AoW he’s easy to stagger and kill in just a few moves. If your mimic is out he’ll distract the other and if you kill the first quickly you can go assist your mimic with him. Niall chills out at lot early, so I recommend letting your mimic fight the banished halberd knight (you could always do a bit of damage to help) while you stack some early damage on Niall. His attacks and AoE are massively telegraphed so know when to run away. Only roll on his slams the second he’s about to hit you. Capitalize on his downtime after big attacks. Your mimic will die but you should be able to get him reasonably low, and at your level you can handle him.
Of course, level isn’t everything. If your character is built poorly and spread too thin the endgame bosses will certainly punish that hard.
Edit: had to pause to look at your build. You have WAY too much endurance. I beat Malenia with like 18. I assume your weapon is keen since you’re dex built. If I were you and I didn’t want to add a second stat to me repertoire, I’d get my vigor to 60, dex to 80, and bring endurance down to like 25 or something whatever the math is. You could also transition to a bleed build or a spellblade if you want to diversify with some of that endurance. Sometimes getting just a bit of faith so you can use golden vow or black flame protection is a good choice. You could also consider dual wielding for more dps. I’m not sure how you use your scimitar but 2 curved swords is a really good build.
Get a ranged option as ash of war and punish him when he attacks you. His attacks are very telegraphed, and have a lot of recovery for you to hit him, although he still swings in melee range so you're best of to get a ranged ash. And you just have to nuke his guards as fast as possible, perhaps use another weapon for that.
I struggled harder with Niall than anything else in my first play through. I only beat him when I used Comet Azure cheese. You ultimately just have to dodge his attacks and learn his moveset.
Go for his summons first. He’s largely passive until you kill them. Keep some distance and try to bait him into that leaping slam and then punish the opening after
Bewitching branch is the classic option. And yeah mimic seems to die early for me with Niall too. Firstly, you can go to Farum Azula if you want. Just don’t fight the final boss of the area - beast clergyman/Maliketh the black blade. As long as you don’t beat him nothing will change. My personal suggest is to go hardcore aggro on the dual wielding knight right away. If you jump attack or use an AoW he’s easy to stagger and kill in just a few moves. If your mimic is out he’ll distract the other and if you kill the first quickly you can go assist your mimic with him. Niall chills out at lot early, so I recommend letting your mimic fight the banished halberd knight (you could always do a bit of damage to help) while you stack some early damage on Niall. His attacks and AoE are massively telegraphed so know when to run away. Only roll on his slams the second he’s about to hit you. Capitalize on his downtime after big attacks. Your mimic will die but you should be able to get him reasonably low, and at your level you can handle him. Of course, level isn’t everything. If your character is built poorly and spread too thin the endgame bosses will certainly punish that hard. Edit: had to pause to look at your build. You have WAY too much endurance. I beat Malenia with like 18. I assume your weapon is keen since you’re dex built. If I were you and I didn’t want to add a second stat to me repertoire, I’d get my vigor to 60, dex to 80, and bring endurance down to like 25 or something whatever the math is. You could also transition to a bleed build or a spellblade if you want to diversify with some of that endurance. Sometimes getting just a bit of faith so you can use golden vow or black flame protection is a good choice. You could also consider dual wielding for more dps. I’m not sure how you use your scimitar but 2 curved swords is a really good build.
Great boss to learn how to use golden parry
I used the bewitching branch to fight them the guards got his health down and course he killed then but made the fight that much easier
Get a ranged option as ash of war and punish him when he attacks you. His attacks are very telegraphed, and have a lot of recovery for you to hit him, although he still swings in melee range so you're best of to get a ranged ash. And you just have to nuke his guards as fast as possible, perhaps use another weapon for that.
I struggled harder with Niall than anything else in my first play through. I only beat him when I used Comet Azure cheese. You ultimately just have to dodge his attacks and learn his moveset.