This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by removing from play all Reptile-Type monsters from your side of the field and Graveyard. This card's ATK and DEF are each equal to the number of Reptile-Type monsters you removed x 600. During each of your End Phases, destroy 1 card on the field.
You can destroy Black Ptera from your field when your opponent doesn't have any cards on the field during your End Phase. Black Ptera will return to your hand and you can summon it again on your next turn. You can keep on repeating this process if your opponent has no cards on his/her field during your End Phase.
You could possibly send multiple Reptile-Type monsters from your deck to your Graveryard by using Magical Merchant's effect. You can then Special Summon Evil Dragon Ananta by banishing all of those Reptile-Type monsters from your Graveyard and Evil Dragon Ananta will gain a lot of attack and defense. You can also fuse multiple Reptile-Type monsters from your hand to Fusion Summon Worm Zero. Worm Zero will gain benefit depending on the number of monsters used in this fusion. And again, you can banish all of those monsters from your Graveyard that is used for the fusion to Special Summon Evil Dragon Ananta.
Face-down monsters aren't considered to have a Type unless you're Tributing them or using them as Fusion Material. For any other purpose, it's essentially typeless.
i had this with 2400 attack, enemy used curse of anubis, i go defense position, 0 defence with 2 monsters, on next turn, my other monster's defence became normal but ananta's defence stayed 0... is this normal??