Lord Retro boss battle is harmless, so you don't need anything crazy other than supplies so you keep your mana up for spells, etc.
The fight is divided into 4 parts: Rookgaard, Thais Castle, Demon Oak and Ferumbras Tower.
- Rookgaard: here your goal is to lure a stone golem to the energy ball in the east side of the room, transform it into an energy elemental. Once it turns into an energy elemental it will explode and turn other stone golems close to it into energy elementals as well, so you'd want to slowly move the golems west close to the parcels. The explosions that transform golems into elementals cause damage to the parcels and once one of them "die" you advance to Thais.
- TIP: The golems are pushable. Use that in your advantage to organise them
- TIP2: Have 1 or 2 players take care of the cake and bug somewhere else that won't bother those dealing with the golems.
- Thais Castle: here you have to toss cakes on Lord Retro's face. In order to do that you need Minor Bugs to kill the cake, then use the cake "corpse" on Lord Retro. Quite straight forward.
- TIP: Have an EK exeta res the Major Bug to the left or right sides of the room. The EK should run up and down (on one of the sides) while exeta res'ing the Major Bug so it doesn't at the CM in the middle of the room. Dead CM = Fail.
- TIP2: Use your battle list to toss the cake on Lord Retro. He moves too much and it's easy to miss.
- Demon Oak: there's a lot going on here but in general this is easy enough. Lots of creatures spawn in this room and your goal is to deal make them step on specific tiles. Repeat the process a couple times and you'll succeed.
- Spoilers go on the red tile
- Bots go on traps (you have to activate them first)
- Major Bugs and Trolls are mostly annoying. You can kill them with the war hammer obtained west of the room after using it on the CM located east of the room.
- Ferumbras Tower: here you need to break the magic walls surrounding Lord Retro, then defeat Lord Retro himself. In order to do that you stand next to the CM who will transform you into Ferumbras. While in Ferumbras form you'll auto cast spells that deal damage to the creatures in the room. Kill 3 of the creatures and use the eggs they drop on the magic wall (not Lord Retro!). Once Lord Retro is out you keep on transforming into Ferumbras and dealing damage to Lord Retro until he's dead. After his death a treasure looking creature spawns in the room. You kill it and that's all!
- TIP: Use summons like demon skeletons to trap the creatures in the room next to corner so you can aim Ferumbras' spells with ease.
- TIP2: Lord Retro "causes a lot of damage" - there's a counter next to your name representing damage, sort of. If this counter reaches 100 you get kicked from the room - so avoid his attacks if you have over 50 on your counter. Standing next to the CM diminishes your counter (this also applies for the past tasks).
- TIP3: Lord Retro runs aways on red health, making it harder to aim the spell on him. Once again, trap him with demon skeletons and "healthy" players and that shouldn't be a big problem.
There's a time limit of about 15 ~ 16 minutes to do all four rooms. I recommend resetting your hunt analyser and keep on tracking that.
Good luck!