No matter what others say, It's freaking awesome. No matter how well you try, people will find some kind of mistakes. But that's good perhaps for the animators.

Which software you used to make it? Flash/Toon Boom or what?

I only gave this 5 stars because it was a pilot, just getting your series idea out the door. There are plenty of issues with this specific animation though. The fight scenes seemed a little bit like they were moving through molasses. The animation was smooth and clean but it just felt like the motions slowed down in the fight scene. The lack of voice actors also caused some issues, like at the end the knight who appeared sounded exactly like the other two blue goblin guys. I thought for a second he was the one speaking. Very little of the idea was actually shown here as well, and I feel that isn't too good for a pilot, nor is a pilot good for an exposition dump. I still think a little bit of story would have went better. perhaps starting a little earlier on to show what was happening in that first scene with the mother and little girl, or showing us more about this Fefnir character.
There was really a lack of dialogue, which I feel hurts the plot a little more.

Loved it!

The fighting wad too slow but a job well done so far. A bit of work on the movements would be helpful.

Nice, cant wait to see the rest of the story.