Knight's & Magic the Complete Series contains anime episodes 1-13.

Mecha otaku Tsubasa Kurata had a pretty good life until he died in a car crash. Now, he's living the life of his dreams. Reincarnated as a young boy, he finds himself in an alternate world where magic is real and humans pilot giant robots called Silhouette Knights. It's this mecha fanboy's chance to shine, and he knows it. Nothing will stop him from building and piloting his very own mecha.