And I drew my new secondary (technically it's tertiary...) rider! This is Kamen Rider Hydra.

Kiriya Kirameki used to live peacefully with his younger brother Takuya. The two being orphaned after Takuya's birth, Kiriya did everything he could to raise his little brother as best he could. This of course led to less than desirable means of making ends meet, with Kiriya having to master thievery to get by. However, the two were happy, as they had each other to keep them going.

Then tragedy struck when Kiriya mistakenly stole from an associate of a group of Purple Dragonborn slavers. Kiriya was knocked out and his brother taken from him by the slavers, leaving Kiriya in desperation. Kiriya made it his goal to get his brother back, and decided that the only way to get him back was to steal from his biggest target yet... a dragon hoard.

However, once inside, he discovered that the hoard he had chosen to steal from was that of the god of the Gem Dragons himself, Sardior. When Sardior saw Kiriya's no-nonsense whatever-it-takes attitude, he was impressed and made the decision to give him the power of a device called the Sardior Driver, intrigued to see how the power would tip the current war between Bahamut and Tiamat. Kiriya uses the driver's power to become the Rider of the Shadows, Kamen Rider Hydra.

Kamen Rider Hydra's powers are channeled from Gem Dragon Scales, which grant him psionic powers. Though he can't change forms, he can use the Emerald, Crystal, Topaz and Sapphire Scales to change the pauldron on his left shoulder, giving him new powers based on those dragons. In addition, his weapon is the Hydraggun, a pistol with a retractable dagger blade in the grip that fires concussive blasts identical to the breath of an Amethyst Dragon.

More importantly, Kiriya was chosen by Sardior for one reason... his wildcard nature. Gem Dragons are neutral by nature, and Kiriya is the definition of a neutral party, not caring for the plight of good nor evil. All he cares about is his ultimate goal of finding his brother and saving him from his captors, and if Raizo and Hayate get in his way, he is more than willing to battle and defeat them.

The powers of the Dragon Head Pauldron are as follows:

Emerald Head: Kiriya is capable of firing a powerful explosion of wind from his left arm. This head also grants him the power of flight.
Crystal Head: Kiriya can set off a blinding flash that renders his enemies unable to see for several seconds, giving him more than enough time to attack or hide. This head also serves as a perfect shield.
Topaz Head: Kiriya can generate a debilitating wave of dehydrating heat energy, making the enemy exhausted. This head also grants increased might to Kiriya's body.
Sapphire Head: Kiriya can unleash a sonic wave that causes extreme pain and severe panic attacks in his opponent. His speed also increases drastically.

Kamen Rider Hydra is my design!