2019-07-12 : Alternative costs, additional costs you could pay, cost increases, and cost reductions are all ignored by Embodiment of Agonies.

2019-07-12 : Embodiment of Agonies checks the mana symbols in a card’s mana cost. For example, a mana cost of {X} is different than a mana cost of {0}.

2019-07-12 : Every Magic card has either no mana cost or exactly one mana cost. A card with no mana cost is never counted by Embodiment of Agonies. A card with a mana cost of {0} is counted.

2019-07-12 : Hybrid mana symbols are treated as the actual symbols, not as either of their two components individually. For example, {B/R}, {B}, and {R} are three different mana costs.

2019-07-12 : If you return Embodiment of Agonies from your graveyard to the battlefield, its last ability counts itself.

2019-07-12 : The mana cost of a split card is determined by its two halves combined. For example, the mana cost of Fire//Ice in your graveyard is {2}{U}{R}, the same as the mana cost of Ral’s Outburst.