The following are some rough numbers to shoot for. Note that these are just general guidelines and not firm requirements. There's 18 individual monsters each contributing something and everyone is going to have different exact teams and setups. Some teams may work with less than the suggested numbers, but at the same time, hitting all the suggested numbers doesn't guarantee your team will work either.
All numbers mentioned here are total stats, including lead and summoner skills. This is because not everyone is using the same lead skills so that needs to factor in.
All frontline monsters: 220k eHP, with at least 1600 def
All backline monsters: 120k eHP (yes this means that your squishy DD like Ardella may need a slot 2 or slot 6 HP% main rune)
In addition to the above survivability requirements, healers/cleansers should have at least 220 speed, the more the better. They will benefit from 100 res and Vio, although neither are absolutely necessary. If you choose to get res, go for 100 or don't bother with any at all. If you aren't running 100 res and also not on Vio, then you should aim to have over 250 speed.
In addition to the above survivability requirements, damage dealers need damage. It's ok if you don't hit exactly 100 CR. It's a good goal to aim for but since you have sustain, you're only look for average damage output and a missed crit won't kill you. 150-160 speed is enough for most damage dealers.
15% is the Acc requirement for R5. Any monster with a debuff should get this, it's not hard anyway.```
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