Legend of the Great Saint He starts as a human but become a demon/magical beast.
Some of them are here : https://hostednovel.com/
The Dungeon Master https://merakiscans.com/manga/the-dungeon-master/
https://whitenovels.com/projets/
In chapter 96 it is said that the Tzedakah Guild has a hostile relationship with Trauka. And in chapter 1180 : "Fire Dragon Trauka’s curse imbued...
Saikyou Mahoushi no Inton Keikaku
Not really a system but still forced to do good deeds : Fake Holy Sword Story ～I Was Taken Along When I Sold My Childhood Friend～
The author released chapter 1271 today.
Douluo Dalu 2 It's not exactly a magician but it's similar
The breath of Xuanwu is the Black Tortoise's Breath. https://en.m.wikipedia.org/wiki/Black_Tortoise
Suzaku is the Red Phoenix, the White Tiger should be Byakko. https://en.m.wikipedia.org/wiki/Vermilion_Bird Edit : too late
Desolate Era Renegade Immortal Coiling Dragon (comprehension of Laws instead of Dao)
The author released chapter 1253 two days ago.
There should be 1 or 2 a week. And there's 5 raw chapters.
There's a manhwa : https://jaiminisbox.com/reader/read/the-second-coming-of-gluttony/en/0/1/
They may not lose their memories if you just reverse their age as the memories seem to be stored in the soul in Death Mage.
https://forum.novelupdates.com/threads/second-life-ranker.85029/page-21#post-5296847
One Man Army : it's not a sect but a guild in a VRMMORPG where he is the only member.
It's from The Tutorial is too Hard
Virtual World : Close Combat Mage Godly Hunter One Man Army ＜Infinite Dendrogram＞ Show Me The Money Shura’s Wrath Zhan Long
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