Activate Ashnod's Altar by sacrificing Izoni, adding CC.
When Izoni dies, Nim Deathmantle triggers, causing you to pay 4 to return Izoni from your graveyard to the battlefield and attach Nim Deathmantle to it.
When Izoni enters, it triggers, creating at least one creature token.
Activate Ashnod's Altar by sacrificing a creature token, adding CC.