Hydra - In greek mythology, hydra was a multiheaded snake slayed by Hercules as part of his Twelve labours.
Hydra and earthworm had one thing in common. You cut one head of hydra, then you get two heads.
Hercules along with his cousin, won hydra in his battle by chopping the head and burning the torso with sword dipped in hydra's poisionous blood.
Raktavija - One of Asuras had acquired a boon from Brahma by penance, which was, for every drop of blood a new self of him was to be born.
So, battle with him was almost impossible. He had too many duplicates of him. So, there came Kali- scary avatar of Goddess shakti consort of alpha god Shiva, and with her huge tongue sucked all the blood shed by the daemon and chopped him and killed him.
Kali (Goddess of destruction) - This is an interesting avatar of goddess Durga.
Kids may get scared if they see the picture of this goddess - why wouldnt they? She sticks her tongue out and garland is made of human skulls and has reddish eyes and numberous hands and one of the hand holds a blood dripping sickle and other hand chopped head of a daemon and the hand below holds a bowl to capture the dripping blood and another hand holds a trident and the hairdo- think of ungreased untied long black hair let loose.
And one more interesting thing to note, after killing Raktavijia she danced happily coupled with rage in the graveyard and on her wounded hubby Shiva who was lying unconsicous among the corpse and she danced on top of him as well, which she didnt realise for very long time and after she realised she came back to her normal form :)
And one another version of her angry dance adds that Lord Shiva was lying among the corpse cautiously. He did so because it was the only choice left to stop her angry dance and bring her to her senses and protect the world from annihilation.
If your wife or girlfriend takes Kali avatar and performs angry dance with all yelling and screaming and if she also has any form of weapon in her hand, lie down and play dead. You will be doing that only to protect the world from annihilation.
Moral of the story : "Not just all that glitters isnt gold" but also "Not all that are blue are Smurfs or Navi from Pandora"
Check more comparison mythology stories here