I will tell you which floors to pick
The guide
Generally, the upgrade floor is the best. The priority of the other floors varies by act. Use common sense and heal if you have 50 health.
- In act 1, upgrade > fight > healing > event
- In act 2, upgrade > recruitment > fight > abnormality fight > healing> boss fight > event
- In act 3, upgrade > recruitment > fight > healing > abnormality fight > event > boss fight
The above is to prioritize winrate. If you prioritize clear speed, because you have an amazing team and experience, you want to skip fights in favor of events (since fights take time). Such people will know to disregard this guide.
Rationale
In mirror dungeons, levels matter the most. Getting 30 on 3 good characters is enough to autoclear every act boss except maybe headless ichthys. Events are fast and generally beneficial, but they add variance, and we don’t want to add variance when levels are 100% consistent wins anyway. Similarly with boss and abnormality fights, they have some potentially bad lineups and we don’t need the upside so no point gambling for it.
In terms of level gain, upgrade gives the most upside and is risk-free compared to fights. Recruitment gives you a level 10-15-20 character depending on the act, so as long as you have a level 10 character that you are willing to swap out, recruitment on acts 2 and 3 is equivalent to getting 5 or 10 levels. This is a trivial requirement, as the character provided at end of act 1 is level 10 and can be left that way. Similarly one of your first 3 sinners can be left at 10 for a long time. As a marginal benefit, recruitment also leaves you with a backup body providing an extra passive. Fights are the third best choice at 5 levels each.
Glossary
I call the floors by names which may not be clear to new players. Here are descriptions of the floor icons, to help identify them:
- Fights have a single sword icon
- Boss fights have two crossed swords in the icon
- Anomaly fights have a cow icon
- Healing has a question mark annotated with a heart
- Recruitment has a question mark annotated with a person and a plus (+) sign
- Upgrade has a question mark annotated with upward-facing arrows/triangles
- Events have a question mark with no annotation
