I saw 2 ways to play Arc Warden.

The hard way is to get several active items and use them in a teamfight together with your clone. So you have double dagon, double sheep, double euls, double everything, together with your hero normal abilities.

But this is too complicated so people just farm one Divine Rapier (or 2.. or 3), a Boots of Travel and just stay in the fountain, teleport your copy to a creep wave and right click the enemy creeps, towers and barracks. It's like playing a even slower and "safer" Nature's Prophet. It's disgusting for several reasons (slow, low team presence, countered by strong push, etc) but still this is what I see people trying to do more.

Still, the power of a good Arc Warden player looks amazing.. but a player who manage to fully tap his potential and dominate the meta will probably make the frog nerf the hero.

Such is the way of the frog.