@Sabotuer99, it's a really easy level to get 5 Gems, especially when you can go back with a maxed out Hero and Goblin's Steam Gun, which absolutely annihilates the boss, as well as everything else in the level. You can also teleport the Hero to the Rogues, so they activate their ability, then teleport back to where the Ents are, and you should kill them quite easily, if that's one problem for you.
Protip for Grinders:
While you're doing something else, you can get free stats just by leaving the Critical Training session on, because of the "Don't Move and you get free Perfects". It may be slow, but it's a way to get free stats along the way as you sleep, eat, etc.
besides, 10 hell portals equals one hall of legends
and although cost of a hall of legends is 200 billion if you are in demon faction, well, you know... it's seriously overpowered
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