ability explanation - Strength of the World

I found a necklace with ability Strength of the world. The ability description reads “Creature deals 20% more damage for each living creature on the battlefield”. Does that mean if my creature attacks while all enemies and my own creatures are still alive, it should be dealing 240% extra damage? If so, it doesn’t appear to be working, because my creature is definitely not doing that much extra.

Thanks

That’s the correct reading of Strength of the World, yes; do note, though, that if your creature doesn’t have a high attack in the first place, you’re not going to get much of an increase either. Drop some attack enchants on there to really benefit.