Reddit user FlurpaDerpNess has shared a pretty sweet and short guide on how to beat Thalnok, fanatic of Crota, the T3 Court Boss. This user managed to beat Tier 3 court of oryx boss is Thalnok few times with a help of group of friends. Here is the step by step guide on he went on to do it.
Step 1
Thalnok spawns at the rift with a Wizard on both sides, in the middle of the ground level a named swordbearer appears along with a lot of thrash mobs covering the area.
Step 2
The boss mechanics are almost similiar to Crota: the boss has a strong shield and becomes immune to all damage except for the sword relic if his shield is broken.
Step 3
The named swordbearer will drop the shield relic nessecary to whack Thalnok's HP away.
Step 4
The two wizards who accompagny him change up the encounter a little bit, while these two are still alive Thalnok's shield will refresh in short intervals, it's very hard to get it down this way so kill the Wizards quickly, like all hive wizards they have a solar shield so make sure some people on your team are carrying solar damage to break the shield quickly.
Step 5
Thalnok's vulnerability window is pretty short and you'll have usually get in 3 heavy attacks, after that back off because he will 1-hit you if you're still close when he gets up.
Step 6
The sword relic lasts long enough to get two vulnerability phases in if you work together, we never managed to get a third one before the sword ran out.
Step 7
After the sword runs out, all of his assets will respawn: the swordbearer, the two wizards and the thrash mobs.
Step 8
The sword's damage seemed to depend on the wielder's light level, our swordbearer was LL300
The sequence FlurpaDerpNess followed was:
kill the wizards, kill the sword guy, burst Thalnok's shield once the swordbearer is waiting on the stairs, whackwhackwhack, burst Thalnok's shield again, whackwhackwhack, back off and repeat. He took just a bit over 50% of his hp in damage each sequence so we only had to repeat once, but there's enough time for a good number of sequences so don't worry if you need an extra repeat.
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