One of the best ways to accumulate free Xes in-game is through Yupir’s Labyrinth. This daily activity consists of 5 dungeons each with 5 stages of increasing difficulty. Only one stage may be cleared per day and entry is granted after every daily reset. Every month there is a new rotation of dungeons to claim your daily free Xes. The breakdown of Xes per stage:

• Stage 1 — 30 Xes
• Stage 2 — 50 Xes
• Stage 3 — 100 Xes
• Stage 4 — 200 Xes 
• Stage 5 — 250 Xes

As there are a total of 5 dungeons with the same Xes reward for each of their 5 stages, the total amount of free Xes a player can obtain monthly 3150 is Xes! That is a substantial amount for free to play players and low spenders. As the first 4 stages are fairly simple for all players, let's review the mechanics for every stage 5 battle to help you pick the units to clear each one.

Clear final stages with ease by understanding boss mechanics

A feature of Yupir’s Labyrinth that players can benefit from is the fact that any stage in any dungeon can be completed at any time in the month. So if you wanted to start the month completing every stage 5 for the first week, that’s entirely up to you. My recommendation would be to wait until a weekly banner for a unit you need and tackle the final stages that week to obtain more Xes for more recruitment opportunities. 

The difficulty in completing every stage in each dungeon stems from the hidden mechanic that is added to each boss fight. When entering a boss fight for any given stage, you need to expect some trial and error in your first attempt in order to try and solve the unique challenge you will have to overcome to win. Luckily, this guide will provide you the details for the current final stages.  

Common characteristics for all boss battles in the Lab, they all have mark/status/debuff/reflect damage immunity. So do not expect easy battles by taking advantage of the unique marks from the Generals (Bathory, Rachel, Shufraken, Jinai, Garff, and Dorka). In addition, this guide will not give you step by step details in how to complete each stage. Every player has different units built and will utilize teams that best suit their play style. That said, minimal requirements for an easy clear that I would suggest before tackling every final stage in the Lab:

1. All units should be at level 75+, preferably level 90, so they can be equipped with a full set of armor. 
2. All units used for a stage should be geared in full fated gear at level 60, especially if you have some units that have not been blessed to a max 6-star grade.
3. Damage dealers should always be burst units at 6-star grade to maximize the burst damage potential. If not using burst damage, units enhanced with Signature Force level 1 are very good alternatives. 
4. Supports and tanks can be 5-star, but not recommended as your mana will be limited.
5. All units used should be +5 enhanced to maximize stats.

Sky Gate 5 — Glenn

The easiest of the five dungeons is the Sky Gate due to it having the easiest challenge and the boss having the lowest CP level. In this stage, the final battle is against Glenn. You can see from the screenshot that his base stats are significantly increased at level 90. In addition, his standard passive is not shown given the fact that it’s been modified to provide Glenn with immunity to nature and fire damage. That said, it benefits you want to bring multiple damage dealers with Burst damage in all other elements. To support your backline offense threats, a strong tank and a cleanse type healer is also recommended to avoid getting stunned from his shock status effect. Utilize a backrow balanced formation with the following heroes for this stage:

1. Frontline Tanks — Garff (or FC Version), Uloom (or FC version), Degas (or FC version), Liechtenstein
2. Frontline Support — Anastasia, Lepin, Iris (or FC version for all if you have them), Kaya
3. Backline — Bathory, Adams, Morris, Deva, Baraka, Jinn (or FC version for all if you have them), and Nermash

Sky Path 5 — Ivan

The next dungeon boss is the legendary hero Ivan. The challenge for this stage is essentially survival. There are four additional units teamed with Ivan and when one dies it increases Ivan’s attack. As the adds themselves do not hit too hard, Ivan can land some serious damage if you decide to kill them off first. He will also cause a lot of bleed damage if you do not kill him fast enough.

That said, definitely bring single target nukers and avoid AOE burst damage as much as possible. Balanced back row with 3 single target burst units and a single front-line healer with a tank is a good strategy here. Also, if your gear and CP level is high enough, you can potentially do enough damage to snipe Ivan in 1-2 rounds with the right setup. Also, if you are at the point in the game where you have unlocked a Signature Force nation, then I would recommend using heroes of that nation as the added damage is extremely useful here. Potential units to use:

1. Backline — Rachel, Baraka, Jinn, FC Deva, FC Adams, Rudley (no FC equipped), Nermash, Deradan, Morris (or FC version)
2. Frontline Tank — Garff, Chati, Uloom, Degas (or FC version), Tantalo (or FC version), Liechtenstein
3. Frontline Support — Anastasia, FC Iris, Lepin (or FC Version), Karin

In addition, as mentioned before, your Burst damage dealers should all be 6-star grade to increase maximum damage output. If you were lucky enough to recruit a FC Iris, I highly recommend using her as your solo frontline unit as her mana boost helps greatly to speed this fight. 

Starry Corridor 5 — Tereia

This third dungeon is a bit tougher than the previous two as Tereia can wipe your entire team in the second round if you are not well prepared. This is a battle of big burst damage or survival as Tereia has a special ability here that does big AOE damage on the first turn of every round. She also applies a decrease dodge effect so your team will not avoid the damage.

Ideally, you would bring 4 strong damage dealers and build up enough mana in the first two battles to burst her down in the first round. If you do not have 4 strong burst damage heroes then you may not be able to kill her fast enough to prevent a second AOE nuke in the second round.

A back row emphasized formation is recommended here with 4 burst damage dealers and a frontline tank or healer to revive. While any burst damage dealers would be viable here, potential units to consider:

1. Frontline Support/Defense
1. Ideal — FC Garff, FC Lepin, FC Anastasia, Kaya
2. Good — Uloom, Degas, Liechtenstein, Karin, Cybele

1. Backline Damage Dealers
1. Ideal — FC or normal Rachel/Baraka/Jinn, Rudley, FC or normal Bathory, FC Annie, FC Rera, FC Adams, FC Deva, FC Brook 
2. Good — FC Rera, FC or normal Otard, Brook, Nermash, Deradan, FC or normal Morris

Abyssal Gate 5 — Rudley

This battle against Rudley can be difficult for anyone if you are not well prepared. The unique skill added to Rudley to make this fight difficult is his ability to counter off every hit while also blinding and resetting his turn if you land a critical hit on him. As his blind is a status effect, bringing a cleanse support unit or having a damage dealer with a machine set or status effect immunity will allow you to handle this issue with ease.

As his counters can do some significant damage if you can’t take him down fast enough, utilizing a protect tank to share damage will be useful here. Lastly, try to avoid using counter type damage dealers or thrust type tanks as he will also counter your counter hits. If you are able to mitigate all his potential damage and avoid getting blinded, then you should be able to tackle this battle with ease.

Also, do not auto battle the first two rounds of trash, use your single attack to build mana to burst Rudley on your first turn in the last round. You can use either a backrow balanced or backrow emphasized formation depending on how many strong burst damage heroes you have. Recommended units for this battle include:

1. Frontline Support/Defense
1. Ideal — FC or normal Garff, Degas, FC Iris, FC Lepin
2. Good — Degas, FC or normal Tantalo, FC or normal Luke
   
   
2. Backline

1. Ideal — FC or normal Bathory, Rudley, FC or normal Morris, FC Annie, FC Adams, FC or normal Rachel, FC Deva, FC Brook
2. Good — Baraka, Jinn, Kirina, FC or normal Otard, Nermash, Deradan

Abyssal Path 5 — Valentina

The final dungeon, Abyssal Path 5, may be the easiest to beat this month with the right team. Valentina has immunity to nature damage and will poison your team whenever she is hit. The damage from her poison is not strong so there is no real threat unless you are incapable of taking her down in 2 rounds. Similar to other battles, you should not auto attack the first two rounds as the AI will burn your mana. If you are able to fully build 10 bars of mana by the time you face her you may even be able to kill her in the first round. If you have all level 90 units with full fated armor then going full damage with a single tank is highly recommended. Recommended units are below:

1. Frontline Support/Defense — FC or normal Garff, FC Iris, FC or normal Degas, FC or normal Tanatalo, FC or normal Luke
2. Backline Damage Dealers — FC or normal Bathory, FC Morris, FC Annie, FC Adams, FC or normal Rachel, FC Deva, FC or normal Brook