Complete guide to defeating all bosses in the Training Dungeon game mode of The Seven Deadly Sins: Grand Cross. Best teams for all bosses included.
Training Dungeon Boss Guide
Guide by 7KDREAMER PLAYS
Note: Not all units are needed and these are not “Team Builds“. They are recommended units for you to bring to make the fight easier. You may not even need to bring all of the units as the fight may be different for each player due to their box.
Training Dungeon – Training Grotto
Training Grotto is available after Episode 109.
Unlocking Dungeon requires Training Grotto Key, which takes 5 days to recharge.

Training Dungeon is now finally unlocked!
Here, players will be able to acquire Equipment Engraving Stones, Hammers of Vaizel and other valuable rewards!
Do not that the Equipment Stats do not take into account here, which is similar to Non-Gear PvP Mode or Fight Festival (Normal).
There are 30 Goddess Ambers available after you open the Dungeon. 5 of the Ambers are randomly selected for the battle.
Players can exchange Ambers for free once per day. The next exchanges cost 1 Diamond each.
The heroes used to clear the Goddess Amber can only be used once per event.
Every time you clear the Goddess Ambers, the Illusion Amber gauge above fills up. Once it reached 100%, it will unlock the Illusion Ambers.
The Training Grotto will close after 7 days, or after you defeat all of 9 Goddess Ambers.
So, when you are actually SO LUCKY as myself to face your own Kingbram team you used against the red giant… what do you do?
Hi! Thanks for the info~ Honestly I’m quite intimidated by the training dungeon, since I haven’t finished working on a lot of my units yet. Could you please provide a bit of advice on who I should prioritize? Box posted:
1: https://imgur.com/t7m7zaB
2: https://imgur.com/Yh0XvbJ
From what I’ve seen, I might want to focus on Elaine, BGuila, Gustav, RSlater, GMeli, and Jillian. I’m missing some recommended units too (RMerlin, Demon Meli, BLiz, etc.) so I’m not sure what to do about that 🙁