sky trial 3-5 beaten!

I was very happy today, I could finally beat sky trial 3-5 boss, without slow, without even an evolved sylph. I used the strategy I described here.

Basically, I tried to have as high HP as I can (with spending all mount whips on endurance, making lvl 9 HP gems etc) - I had nearly 300k HP. And used everything to survive without significantly reducing my damage: a lvl 8 heal, a lvl 9 guardian rune, illusion and enhanced regeneration astrals. I used a 2-star purple Hades, with 5x lvl 5 dark resist crystals, I had 370 dark resist. Originally I thought 250k HP and 500 dark resist is necessary to survive, but 300k HP and 370 resist was enough. My gems are MATK / Crit / PDEF / HP, but for this occassion, I converted all PDEF gems to MDEF since this boss is MATK. Of course I used all available potions and scrolls.

I couldn't make a video, but it went basically this way:
First I did a "pre-run", used just lightning both to have max rage and sylph ready to awaken.
Then, a second run, where I opened with suntoria, awakened, guard rune, used sylph skills (scoring a few double hits here is important!), Hades heal attacks and heal rune could keep me healthy, then I reverted back. Thunderer / Suntoria / critical restoration (don't use guardian angel!) and guardian rune take me to the second awaken. With enough crits, Hades could finish off the boss just when he went berserk. I took my like 10 tries until I got it.

So the key tricks were:

• Have high HP so suntoria, heal rune and crit heals have max efficiency.
• Use Hades so I have high dark resist and I can heal while dealing damage.
• Maximize survival (mdef, block, enhanced regen, illusion, guardian and heal rune).

I guess your question is now, what is my advice for a knight or archer. Percentage damage reduction is the key here, and it's done via Hades. Knights and archers really don't need Hades, and you shouldn't build one just for sky trial. There are many ways, though, where you can surpass me: you can make lvl 6 dark resist crystals, refine your goddess blessing astral to epic heights, have 350 or even 400k HP, and have lv l0+ heal and guardian runes. Also your Hercules / Triton etc can be definitely stronger than my 36k BR unevolved Hades. Knights also have extra damage reduction and archers can kill faster, so I think there is hope for everyone. Good luck!