Fatalis Duo - SwitchAxe & Sword & Shield [Monster Hunter World: Iceborne]
This video isn't a guide but I will provide my thoughts below.
This is a tough fight no doubt. So make sure you are prepared and built for it.
Our setup is me on SwitchAxe and Rykin on SnS support.
Make sure all of your armor is fully augmented and upgraded to the max level. Rarity 12 has a max upgrade level of 20 if you are MR100+
For any DPS role, here are the skills you should prioritize;
-Health Boost
-Fire Resistance
-Defense Boost (I know this one will be questionable so up to the player's discretion)
-Divine Blessing (If you don't get Defense Boost)
-Part Breaker
-Agitator
-WEX
Then the remaining skill slots will go towards the weapon style you choose.
For the DPS player, always focus the head whenever possible. It won't matter if you do a lot of damage but don't break the head and then die in the final phase due to its fire damage increase. Try to break the head in the second phase or early into the third phase. You will most likely die in one hit from any of its fire attacks in the final phase if you did not break the head at least once.
The support player focuses on... well, support. Buffs, healing, and we fitted our support with Heavy Artillery so they can use the Roaming Ballista, Ballistas, and Cannons if needed. The key to the support role is to know the monsters' tells and attacks. If your teammate gets caught off guard and gets attacked by a hard-hitting attack, you have to be ready to heal them.
Always try to wall bang Fatalis into a wall as much as possible. Make sure the head is wounded to add part damage when slamming. Keep in mind it has to be on all 4 legs for the clutch claw flinch to wall bang it. This will also help up keep agitator.
If there is anything I missed I will add it here later.
Monster Hunter World
Iceborne
Installed mods:
-Souvenir's Light Pillar