Activate Ashnod's Altar by sacrificing Mesmerizing Benthid, adding CC.
Mesmerizing Benthid dies, triggering Nim Deathmantle, causing you to pay 4 to return Mesmerizing Benthid from your graveyard to the battlefield, and attach Nim Deathmantle to it.
Mesmerizing Benthid enters the battlefield, creating two 0/2 Illusion creature tokens.
Activate Ashnod's Altar by sacrificing an Illusion, adding CC.