With the introduction of everything coop patch, we are now able to farm the limited time dungeons with our friends (or in my case, myself) for half the stamina. There are probably countless variations for a button team for PreDRA Infestation, but here is a relatively easy to form and mostly farmable team. The other subs are just for skill boosts and outside of the 3 poisons (or true damage), the Lucifer needs to have a skill inherited to counteract the 2 turn skill delay from the boss. Please excuse my lack of recording skills and pointless audio.
As always, it is more efficient to run the easier difficulty as it awards more Monster Points per stamina spent.