From level 80 you will get a quest from Amos in Aven to solve the Temple Knight's Trial. Temple Knight's is a heavy dungeon and can only be mastered with 5 players, as every boss is spawned by talking to an NPC. Each of these NPCs must be talked by a different player. This means that you can only talk to one of the NPCs and this turns your skills into a Boss skillset. TK has an extremely short time span. As soon as you talk to the NPCs the clock is ticking and you have just a few minutes per boss.
Easy way is to discuss an order here in advance. It is best, the strongest in the group takes the simplest boss and the weakest the toughest.
I'm taking an Annihilator for the entire Temple Knight's Trial to break them (because of the trophies) - The weakest in the group should go Annihilator Class and talk to the 4th NPC, because the 4th Boss does not need an Ammo and for the 4th Boss you need all power, which is possible. To defeat the 4th boss successfully and in time, do not kill both!! Bring both HP bars down to a thumb width and then kill. When one is dead, the other spawns again - so you have to kill both at the same time and the time is ticking, be fast!
It will be hard without strong gear, but hard work will be rewarded - the quest gives you a great reward: the title "Temple Knight". This title gives you 10% on all your stats!
Boss 1 "Faya" -> elemental weakness: darkness
Boss 2 "Yukari" -> elemental weakness: lightning
Boss 3 "Carol" -> elemental weakness: nature
Boss 4 "Natalie" and "Reeft" -> breaks on every element
Boss 5 "Augustus" -> elemental weakness: light
Why is Temple Knight's Trial still done every day anyway?
In the Temple Knight's Trial (short: TK) you can get extremely strong trophies and rings!
The combination of these sets give huge boosts and are indispensable for many classes.
Which Loot can You get?
Temple Guard Gem, Guardian Knight Gem (P-ATK oriented)
Temple Warcry Gem, Knight's Warcry Gem (P-ATK oriented)
Temple Wisdom Gem, Knight's Wisdom Gem (WIS oriented)
Temple Blessing Gem, Knight's Blessing Gem (M-ATK oriented)
Temple Guard Ring, Guardian Knight Ring (P-ATK oriented)
Temple Warcry Ring, Knight's Warcry Ring (P-ATK oriented)
Temple Wisdom Ring, Knight's Wisdom Ring (WIS oriented)
Temple Blessing Ring, Knight's Blessing Ring (M-ATK oriented)
By the way
You can buy the rings!! If you are in a hurry and You do not get your ring, You will earn points per TK run. If you have 60 of these Temple Knight Insignia (meaning the currency) You can buy at Tyrosen in Aven (X: 325, Y: 275 ) under "Exchange for Temple Knights' Hall Rewards" the rings You need.
-> This only works with the rings, not with the trophies.
This dungeon can be made only once a day, you better relog before you enter TK, because if you disconnect, you will not come back in and your chance for this day is over.