Three guys with 280KK HP (280 000 000) and nonstop mutual healing... Is this normal? Any tips?

Durny_Sabaka,

Unfortunately, as far as I am aware from other youtube videos and forums, that is normal for that level.

There are some strategies, although minor, that can help work in your favor. For the most part, that level is a DPS check for your character.

The three opponents you come up against will all have the ability to heal mutually as well as themselves and for significant amounts. In addition, each opponent employs a unique ability as well.

Opponent #1 - Will bestow a shield that can last 2 turns. Do NOT focus your DPS attempts on a shielded target!
Opponent #2 - Will use a Regeneration spell that can last 5 turns that heals for smaller (still difficult to DPS through) amounts than his heal. Do NOT focus your DPS attempts on a Regenerating target, if possible!
Opponent #3 - Will cast a debuff spell on your character, lowering your offensive damage by half.

Their weaknesses are as follows:
1) It takes them generally 1 turn to switch their attention to healing an ally.
2) It takes them 2-3 turns to be able to heal, use their other special abilities again once the ability is used.
3) All of them are vulnerable to stuns, confusion, debuffs, etc.
4) Opponent #3's debuff can be erased by drinking a Biboo's Brew's potion (Doubles your offensive damage for a few turns).

Now, I can only tell you what worked for me.

1) I have at least achieved Soul Master status in all stats.
2) Used money to upgrade Stat gain in training. Max this out.
3) Used money to upgrade Exp gain. Max this out.
4) Be sure to buy all the 4-leaf clovers (Silver Clover, Golden Clover, Soul Clover). The clovers gained potentially translates to free points for your stats.
5) Once you max out your Crit rate, Dodge Cooldowns, Block Cooldowns, etc, focus on training in Melee and Defense only. You will only get marginal upgrades from other forms of training.
6) Any points gained from leveling up goes directly to Melee. No exceptions.

I attempted this fight again after reaching at least 400k points in Melee and roughly 350k points in Defense.

I used a 2-handed sword with rings that gave +increase in damage to Melee, and +heal a percentage when doing a Super Crit. I do not believe the other rings were really necessary but these were the most helpful to me.

1) I switched targets between Opponent #1 and #3 after each normal strike.
2) Saved all my special abilities until I was able to throw a Confusion dagger (that random ability) that last 2 turns on one target.
3) Immediately stunned Opponent #3 (or Opponent #1, whichever was not Confused). Immediately Switched target to Opponent #2.
4) Immediately drank a Biboo's Brew Potion.
5) Used all remaining abilities in a specific order:
-a) Archery (the space bar ability);
-b) Magic abilities;
-c) Poison Arrow;
-d) Omnisoul.

This did not kill the target outright but it did whittle it down enough so that I was able to kill the target before the confused opponent recovered. This still required quite a bit of luck and is not a guarantee as Opponent #2 can still get a heal off. In my case, I was able to follow up my [Mega] Omnisoul with a Super Crit normal attack.

Once your target is down, wait until your abilties are off cooldown and repeat the process again on the remaining two targets. The rest of the fight will fall through easily enough.

As stated before, this is what worked for me. If you find anything of use, feel free to pick and choose until you find a strategy that works for you.