Mia
Sam thought for a bit and tried to think of an appropriate name, after some thought, he still doesn't know what would be appropriate for a hydra which might possibly become a variant in future.
After some consideration, Sam decided to name it Mia. Not because he thought it is appropriate, but he came to a conclusion because he knew that he would never be able to decide whether any name would be appropriate or not.
And to justify himself Sam said. "As Shakespeare said, what is there in a name? A rose by any other name would smell as sweet and no matter what you are named you will still be the strongest hydra who stays forever by my said. So, your name is Mia."
Sam patted the heads of her as he said this. Mia seemed to be happy as it snuggled even more comfortably.
Even though, Sam liked this he has another problem at hand now and that is to improve the hydra quickly.