At first, this fight may seem almost impossible, as every time you draw in close to this boss, he teleports further away. It's just a matter of timing.
Gwyndolin has 3 attacks which are all pretty lame.
1 - He will shoot multiple arrows at you
2 - He will shoot multiple homing magic projectiles at you
3 - He will shoot a large magic projectile at you
The first two attacks cannot pass through the pillars on both sides of the hallway, so in a worst case scenario, you can use those as cover. The third attack, however, can go through those pillars, so it's best to try and dodge all of his attacks if possible (which isn't a very hard thing to do).
When he does his arrow attack, he will slightly raise himself up, this is the best time to run in for an attack. Try not to get too close to him until he raises himself up. Once he is, sprint forward in a zig zag pattern so you can avoid his arrows, and being attacking him. Repeat the process until he's dead.
Gwyndolin's death will get you Soul of Gwyndolin and 48,000 souls
![](https://i.ytimg.com/vi/KEe66G23Xds/maxresdefault.jpg)