it's all about range. in this game RANGE is most important especially if you are T4 player and you are fighting against t5 players. if you use eagles or wyverns you will get destroyed during wars, on the other hand with celestials from the range you can have at least some impact attacking enemies from the range. it's not all about stats, gameplay is more important.
how are eagles worse than wyvern and celestials? also wyverns have higher base stats than celestials
it's all about range. in this game RANGE is most important especially if you are T4 player and you are fighting against t5 players. if you use eagles or wyverns you will get destroyed during wars, on the other hand with celestials from the range you can have at least some impact attacking enemies from the range. it's not all about stats, gameplay is more important.