I'm a TH9 and I was zapped by a TH10 yesterday. 5 lightning spells... I can understand a TH7 zapping higher THs, but a TH10 zapping a TH9? That's sad.
Is it worth it? In the time it takes to make 5 lightning spells, I could have raided many times the amount of DE they could possibly gain with those spells, while making gold and elixir in the process.

