I _think_ I discovered a bug. Don't go past um_dun02 towards Niflheim. There's no warp back once you get to yggdrasil01 map (unless you die). Also, there's no MVP (Lord of Death) in Niflheim.
I thought the gamemaker would be more active in this stage of the game, hunting bugs and balancing the game. He has a gem in his hands, but apparently doesn't have the time to keep up. Lowered my rating from 4 to 2.
A good place to make money and also get a decent card to put on weapons is Toy Factory (xmas_dun01 and xmas_dun02). Myst cases drop pearls (3000z) and pieces of cake (1500z). Cruisers drop Cruiser Card, which gives 10% more dmg on criticals.
Just a notice for the ones aiming to grind prestige, it seems to be bugged: i've got all 4 talismans, prestige increased to 315, reset the game, got again the 4 talismans and the prestige stayed still. Reset the game, lost everything and the prestige remained the same, 315.
If you look at the high scores, everyone is maxed at 315 prestige. Since it takes _forever_ to get all 4 talismans, I suggest to fool around with level high scores by now, until prestige gets fixed.
Materials should be stackable, so you don't lose the chance of getting more of them in the early game neither they clog up your inventory later in the game
 "Idle Raiders: Second Run"){kind=icon}
 "Ragnarok Idle"){kind=icon}
 "Infinite Spreadsheets"){kind=icon}
 "Rat Clicker"){kind=icon}
 "Auto Turret"){kind=icon}
Coming up with next update!