In Monster Harvest, you put your own Planimals against wild ones in the dungeon. This is how you stay safe and manage to loot the dungeon in relative safety. But sometimes, you'll come across higher leveled Planimals that you have no hope in defeating.
In short, you cannot run away from battles in Monster Harvest. This is entirely due to a soil upgrade mechanic. By letting your Planimals die, they become hearts that you can use to upgrade your soil and the starting level of your beasties.
You need your Planimals to die, so you can make them stronger in the long run. It's a never-ending cycle of growth and death. If your soil is level one, then all Planimals grown will always be level one. When they die, they will drop one heart. You use those hearts to level up your soil.
If your soil becomes level two, then the default level of all grown Planimals will become level two, and when they die will drop two hearts. Which you then invest into your soil once more. This makes it easier to dive deeper into the dungeon because your Planimals will start at higher levels.
This is why you cannot run away from battles in Monster Harvest. Your Planimals have to die.
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