Dr. Doppler

"How do you feel now, Sigma? Did you like my special vaccine for the Sigma virus? X, I'm sorry to have given you so much trouble. I know I can never really atone for what I've done... But I will try to set things right by taking Sigma with me!!!"

- Dr. Doppler

Dr. Doppler (Ｄｒ．ドップラー) is a reploid scientist who serves as the main antagonist of Mega Man X3. Prior to the game, Doppler became famous for having seemingly created a vaccine to the Maverick Virus, and built Doppler Town with the assistance of the 'reformed' mavericks who congregated around him. Unfortunately, it soon turned out that the "vaccine" was a placebo, and more Mavericks were created as a result. Doppler then became the leader of the Doppler Army, an army comprised of some of the most powerful Mavericks the world had ever seen.

Later on in the story, it is revealed that Sigma took control of Dr. Doppler and forced him to create a new battle body for him. He also rebuilt Vile, and hired Bit and Byte of the Nightmare Police to destroy X and Zero. Doppler himself is fought at the end of Doppler stage 3, where he is vulnerable to the Acid Burst. Upon being defeated, Doppler comes to his senses, telling X about Sigma's new body and where to find it. What happens to Dr. Doppler's afterwards depends on whether or not Zero is still active. If Zero is still active, Zero comes in with Doppler's actual Sigma Virus vaccine equipped on his saber and incapacitates Sigma. If Zero had to go back to Maverick Hunter HQ for repairs, Dr. Doppler will take Zero's place, but he will use the vaccine on his own body and sacrifice himself to stop Sigma. Either way, Dr. Doppler has made no subsequent appearances, and his true fate is unknown.

Pre-Battle
Doppler: I've been waiting for you X. I'm Dr. Doppler. I've been watching your battles closely. Your victories over my men have been most impressive. I need superior reploids like yourself, X! I offer you the chance to join us. Together we shall build a Utopia where the Reploids rule under the watchful eyes of Sigma, our lord and master.

X: No way, Doc! Your schemes end here and now!!

Doppler: Perhaps you are not as smart as I once thought! Prepare to be ripped apart and to be born again as part of the new body of Sigma!

Defeated
Doppler: You are strong X... Strong enough to defeat Sigma...

X: Doppler, can you talk?!

Doppler: Sigma's true form is that of a computer virus... I was corrupted by him and... I created a horrific new body for him...

X: Where's the body now?

Doppler: It's in the underground hangar of this lab... I don't think Sigma has occupied it yet... Don't worry about me... Destroy the body before it is too late. Time is running out...

X: Thanks Doc...

Quotes from Mega Man X3

 * "He is the Maverick Hunter I failed to catch last time. I had no idea he is so powerful... Bit and Byte!"


 * "Bring that Maverick Hunter to me... alive if possible." (To Bit and Byte.)


 * "Watch your mouth or I'll put you back where I found you. Even with your enhancements, you are still no match for me. (To Vile Mk-II.)


 * "Fine. Just make sure you do it. I still can't believe that Maverick Hunter defeated my master twice in the past..."


 * "How do you feel now, Sigma? Did you like my special vaccine for the Sigma virus? X, I'm sorry to have given you so much trouble. I know I can never really atone for what I've done... But I will try to set things right by taking Sigma with me!!!"


 * "X... it's... time to say... goodbye..."

Trivia

 * As with Mega Man X4, fans like to debate which of the two endings is the canon one, since there is no solid indication in the series. While Dr. Doppler hasn't made an appearance in subsequent games, his anti-virus technology seems to live on, most notably in Mega Man X5.
 * It is worth mentioning that if Zero uses the anti-virus on Sigma, he says that he will come back. However, if Doppler is the one who destroys Sigma, he does not say so. This may hint that the canon ending is the one where Zero destroys Sigma.
 * In Yoshihiro Iwamoto's Rockman X3 manga, Dr. Doppler is a colleague and best friend of Dr. Cain, who was deeply disheartened to see his friend's descent into rampancy. Towards the end, Doppler was able to briefly return to his pre-maverick self, before opting to commit suicide rather than revert into a Maverick by ripping his own innards out.
 * Dr. Doppler shares the same name with a character from Disney's Treasure Planet. That Dr. Doppler's first name is Delbert, whereas this Dr. Doppler's first name remains unknown.
 * Dr. Doppler's name may be a reference to the Doppler Effect and a pun on Doppler Radar.
 * Doppler is one of a handful of prominent Reploid/Maverick characters from the X series not featured in the Worlds Unite crossover event from Archie Comics. No explanation is given for this, but it is possible that it was because Doppler helped bring about Sigma's defeat in X3.