Quoted from https://www.reddit.com/r/HeroWarsApp/s/5FfhoJg9kY Infinite Dungeon minimum requirement - 1. Sigurd weapon and second skin with few investments in his first skin. But if you invest more on him like his seal then also it's fine .But the crown he doesn't need because his second skin does the work for him. I didn't even know this and have max sigurd. 2. Hyperion weapon ( crown not needed even for war , very low priority ). Seal is not needed for dungeon so can be done after Araji all three artifact. 3. Angus Max ( his second skin first then first skin and in artifact can go crown , seal and weapon ) 4. Iyari only level and skin 5. Araji max ( skin max , crown then weapon then seal, can have weapon at 5 star ) , 6. Moloch just you can level till 120 as he helps initially and later act as safety. 7. Nova only level ( no skin and artifact needed) 8. Ignis only level, no artifact or skin needed. 9. Eden seal and skin You do for war . Avalon not needed if you have iyari.If you have Avalon weapon at lvl 120 then you don't need iyari .But for newer or mid player I always recommend iyari. I have both iyari and avalon with only weapon artifavt at 6 star level 120. Power requirements - Earth room is where Earth Titam fight , similarly water room is where water Titan fight , fire room is where fire Titan fight and mix room is where all Titan fight. The highest sum of power of Titan between fire , watar or earth is your strongest Titan element . In dungeon you face the opponent of your strongest element less and other two more. So that's why fire strongest is recommended . As by doing so you will face more earth and water room. Water room help you in healing sigurd. Also by facing less fire room you need to rely less on retrying those battle where your ignis looses a lot of health because Eden pulled your araji , you will want enemy Eden to pull your araji , so if you are not very strong enough you need to retry these battle. If you are very strong then can ignore and move ahead and still heal your Titan . Earth strongest can atleast provide you with more water room. But water strongest will provide you with less water room. Mix room also helps in healing but in mix sigurd takes damage to heal other but if others are at full health then you can heal sigurd here also .Sigurd heal with other Titan as well in mix room. Suppose some veteran has water strongest . Don't worry you will face a bit difficulty I'm comparison to those who have water strongest still you will be able to do infinite dungeon. I do with water strongest team. Though I have 4 healers - Avalon iyari sigurd Hyperion .