One shotters in Arena - what are their builds?

[Thakos]

I regularly stumble across units in the Arena that one shot me. Take Telestio as an example.

He does his S3 one time and 2-3 people die. My team consists of Zero, Lilaha, Rena, Labyreth. So with the last two units I already get big damage reduction, but that isnt big enough.
I got every HP and Defense-Bonus activated from Level 3 to Max.

When I use Telestio, he has: Dual wield , (one weapon is Trishula), 4300 Int around 250% DMG-Bonus (for elements of course) and damage bonus against type and attribute. With this I can halve the enemy team`s HP at best.

Same goes for Lilaha. I see people one shotting me with 3800 years ago or Galaxy. When I use Galaxy however, well 20% of the enemy`s health are gone. Lilaha has naturally waaay more damage-bonuses than Telestio among her zero-sc-cost skills. So this is even more ridiculous.

So either I miss a huge damage bonus in my sc-skills. Or the enemy has a damage reduction that is way better than mine.

(And no it is not the case that I pick fights where Labyreth AND Albedo are in the enemy`s team).

Has someone a (nearly) one-shotting build for Lilaha/Telestio?

Thanks in advance!