Lever Bosses

Lever Bosses are Bosses which can only be fought by a limited number of players at the same time. In order to limit the number of players, there is a room before the boss room with special tiles on which players cannot stack and a lever. When the lever is pulled, players in the special tiles are all teleported together to the boss room. As long as there is at least one player inside the boss room, the lever cannot be pulled again. 
During fights against Lever Bosses it's not possible to use Special Summons as well as the spells Chivalrous Challenge and Divine Dazzle. 
Most Lever Bosses leave their loot inside Reward Containers. They are usually repeatable bosses with a time cooldown (mostly 20h), but some of them have other restriction systems (e.g. Prince Drazzak) or no restrictions at all (e.g. The Ravager). 
== List of Lever Bosses ==
Note: several bosses have multiple forms, stages or even minibosses before the final boss in the same fight. In these cases only the main/final boss is listed. 
* Tirecz
* Horadron
* Prince Drazzak
* Terofar
* Zavarash
* Death Priest Shargon
* The Ravager
* Ferumbras Mortal Shell
* Mazoran
* Plagirath
* Ragiaz
* Razzagorn
* Shulgrax
* Tarbaz
* Zamulosh
* Anomaly
* Eradicator
* Outburst
* Realityquake
* Rupture
* World Devourer
* Gelidrazah the Frozen
* Lady Tenebris
* Lloyd
* Melting Frozen Horror
* Soul of Dragonking Zyrtarch
* The Enraged Thorn Knight
* The Time Guardian
* The Last Lore Keeper
* The First Dragon
* Essence of Malice
* Ravennous Hunger
* The False God
* The Sandking
* The Sinister Hermit
* The Souldespoiler
* The Unarmored Voidborn
* The Source of Corruption
* Last Planegazer
* Brokul
* Grand Master Oberon
* Ghulosh
* Gorzindel
* Lokathmor
* Mazzinor
* The Scourge of Oblivion
* Faceless Bane
* Alptramun
* Izcandar the Banished
* Malofur Mangrinder
* Maxxenius
* Plagueroot
* The Nightmare Beast
* Count Vlarkorth
* Duke Krule
* Earl Osam
* Lord Azaram
* Sir Baeloc
* King Zelos
* Urmahlullu the Weakened
* Scarlett Etzel
* Brain Head (does not use a lever per se, but the same rules apply)
* Thaian
* The Dread Maiden
* The Fear Feaster
* The Unwelcome
* The Pale Worm
* Drume
* Goshnar's Cruelty
* Goshnar's Greed
* Goshnar's Hatred
* Goshnar's Malice
* Goshnar's Malice
* Goshnar's Megalomania
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