Hi!
This is my concept for your new logo.
It contains a letter D that I transformed into a ninja. I included the color that was requested. Ninja's eye shape is made to copy a space between headband and scarf. There are no gradients used, shading is done via different colored vector shapes. I also made a small shuriken and placed it instead of the dot above the letter 'i' for the final touch.
Everything can be edited to achive your desired results.
Thank you for the opportunity!