Most likely something to do with inc att (on the hero), decrease def and weaken (on the CB).Most likely something to do with inc att (on the hero), decrease def and weaken (on the CB).

Also does that 14k-18k damage is when the critical hit procs or normal hit? (Because you only say about same ATT and Crit Damage but say nothing about crit rate)

Do you have the same masteries and gear? How about HP? Lugan's default skill is base on  hp

What video are you referring to? 

There are other factors that could affect damage like buffs on your Lugan, debuffs on the CB, masteries, and even the difficulty of CB you're hitting. 

I hav e Question why do i only have 30 multi battles when others have 100

My team 

Selpucher 1300 attack, crit dmg 94%.

She hit with crit dmg is 35000-40000(no decrease def, weaken)

LightSworn 1000 attack, crit dmg 113%

 42000-50000 crit dmg, skill 2 is 70000-80000( (no decrease def, weaken).

Lugan, 1k7 attack, crit dmg is 122%

14000-18000 crit dmg....

other champion with lower attack and lower crit dmg and hit harder than Lugan hit.

1. Every hero have a different multiplier, so 2 different heroes can have the same stats but different damage output, unfortunately Plarium does not openly state how much multiplier each hero has.

2. Each hero have different stats on which they scale up their damage, Sepulcher and Lightsworn all of their damage scale from DEF stat, their att effect nothing on their damage output. And I have googled Lugan, his A1 scaled of HP, and his A3 scaled of Att, but his A3 is AoE on which usually have a lower damage multiplier than single target attack.

So need a bit more clear data, why don't you screenshot all 3 heroes with the complete stat being 

thanks you, I updrage again Lugan now he better