Actually someone on this forums DOES have 5 Druids and DOES do Arena with them. And DOES use Stealth and 15x Treants.



If you do enough searching you'll work out who, maybe send them a PM. They dont like to be famous and they dont make videos or screenshots and they enjoy the quiet life and not all the attention.
But yeah someone has tried it and apparently its very fun.



Hope that actually answers your question vs getting told to try it for yourself.