No record :-(
After you killed the mobs, use the Mistlock Singularity to reset cooldown then the teleporter to enter the boss area.
Mai Trin is protected by ten stacks of Captain's Shield, each stack reducing her incoming damage by 10%. The only way to remove stacks is by pulling her into electric fields from Horriks alternating projectiles. Standing in the electric field will remove one stack per second from her. The fire field projectile from Horrik can be reflected and absorbed. You can easily recognize the projectile type from the icon above the targeted player.
Every 25% health, Mai Trin disappears and additional enemies will spawn while fiery cannons start shooting. Switch your damage to Horrik and deal 25% of his health to make Mai Trin return. Cleave the spawning mobs during downtimes.
Keep in mind that with each phase more cannons start shooting at you, the fight can get quite chaotic in the last phases. Luckily, Mai Trin won't have any protecting stacks below 25%, so make sure to finish her rather than Horrik (Killing Mai Trin finishes the fractal).
It is favorable to run for projectile absorbtion with and condition cleanse with . Recommended to use the Salvation / Invocation / Renegade trainline combo variant for more energy for the whole fight. Do not forget that (Staff 3) can block Horrik's projectile if you stand into it!
You can block Horrik's cannon projectile with (Greatsword 4).