Nekusar makes everyone draw an extra card each turn, and all opponents lose life every time they draw cards
The arch is destroyed, and the Fugitive Doctors biology and memories are restored
And since it has the 'Flying' tag too, you should be able to hit your foe on the regular
It pairs well with other cards that want you to send artifacts to your graveyard, like Marionette Master and Myr Retriever, and the ample self-mill found in these colors like Grisly Salvage
One part of the card that seems overlooked is that each player loses life and then the player who revealed the fewest loses half their life
In a case where you put more than one +1/+1 counter on Etched Slith with its last ability (for example, because of the effect of Doubling Season), the reflexive ability will trigger once for each +1/+1 counter you put on it this way