Part of the main mission - cannot be missed. Points to look for during the fight for ease:
- He is weak against fire. Marceline’s fire special attack and fire gems added on basic hits for Jake and Finn will help to get him down in HP. His total HP is 2100.
- He will have two (2) minions with him during the fight. Concentrate on the minions and get them down first - they are the twin fighters which means they hit twice on each of their turns.
- Fern will suck away your special attack energy - do not conserve. If there is a special attack to use, use it or lose it. Batteries could help charge up the meter on Marceline’s turn, but wait for her to use it. He will generally suck out about 5/6 points of energy.
- Fern does three (3) power ups on himself: Attack Up, Speed up, and Agility Up
- Fern will do a double vine attack when he gets to about half his health.
- Stay on top of the health potions - 25% ones should be fine. If you are leveling the characters as much as possible along the way - extra focus on attack and HP leveling - there should be no issues with maintaining health as you may be level 5 by the time reaching here (level 4 minimum, in my opinion).
Not a hard fight. Take your time and it will be over in no time.