Special Summon 2 "Doomsday Tokens" (Fiend-Type/DARK/Level 1/ATK 0/DEF 0) in Defense Position. These Tokens cannot be Tributed for a Tribute Summon, unless it is for a DARK monster. You cannot Summon other monsters the turn you activate this card (but you can Set).
While you may not Summon monsters the turn you activate Fires of Doomsday, you may use these cards during that turn to utilize your tokens. Creature Seizure is able to force your opponent to trade one of their monsters with your tokens. Order to Charge can enable you to sacrifice 1 token and destroy your opponent’s monster. Enemy Controller is one of the options to sacrifice 1 token in order to take control of your opponent’s monster.
You can't summon him the same turn you activate this, you can only set. If your opponent has a monster with 2100+ Atk then it's a waste. Use it to set high defense dark monsters with a flip summon effect