If you haven't heard about Cecil the lion, here's 10 reasons you should hear his story.

1) Outrage has erupted on social media over the senseless killing of Cecil, a beloved Zimbabwe lion. Cecil was lured out of his sanctuary at the Hwange National Park, shot with an arrow, and killed 40 hours. Cecil suffered a slow death according to the Zimbabwe Conservation Task Force.

2) Zimbabwe is now asking for the United States to extradite American Dentist and recreational big-game hunter, Walter Palmer, who shot and killed Cecil.

3) According to the the Zimbabwe Parks and Wildlife Management Authority and Safari Operators Association of Zimbabwe, Cecil was killed illegally.

"I relied on the expertise of my local professional guides to ensure a legal hunt," Palmer said. "I had no idea that the lion I took was a known, local favorite, was collared and part of a study until the end of the hunt," Palmer said, according to CBS. "I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion."

4) Despite his statement, Palmer has received massive backlash.

5) A petition statrted on change.org calls for the United States Fish and Wildlife Service (USFWS) to release their final rule on the listing of the African lion under the Endangered Species Act to help prevent imports of trophy animals killed. It also calls for those involved in Cecil’s killing be held accountable. The petition already over 600,000 supporters, but their goal is 1,000,000.

We're strongly against the illegal poaching of animals. Sign this petition if you feel the same. Justice For Cecil. https://t.co/WJDQRDkdgE
— SWIM DEEP ≈ (@SWIM_DEEP) July">https://twitter.com/SWIM_DEEP/status/6267109852026... 30, 2015

Signed this because how can you not... #CecilTheLion https://t.co/vyvxYtu9nw
— Joe Boyd (@thisisjoeboyd) July">https://twitter.com/thisisjoeboyd/status/626786937... 30, 2015

Justice for #Cecil the iconic collared lion slaughtered by trophy hunter! https://t.co/esUQVzxTsl via @CdnChange
— robsalem (@robsalem) July">https://twitter.com/robsalem/status/62676804809606... 30, 2015

6) Many have also taken to twitter using the #justiceforCecil.

Just because a day has passed,let us not weaken our resolve... #justiceforcecil Goodnight tweeties,we are a powerful voice if we unite.
— Lisa Vanderpump (@LisaVanderpump) July">https://twitter.com/LisaVanderpump/status/62662731... 30, 2015

R.I.P. Cecil. We pledge to end wildlife crimes. #JusticeForCecil http://t.co/aK3KPg9vqI
— Paige Nelson (@dolphinpaige) July">https://twitter.com/dolphinpaige/status/6261778665... 28, 2015

7) Jimmy Kimmel even payed tribute to Cecil and addressed how senseless his killing truly was.

8) People have made massive donations for conservation efforts, according to Oxford University's Wildlife Conservation Research Unit. Over $470,000 has already been raised.

9) People have also created shrines in honor of Cecil and plan to hold protest against Walter Palmer.

10) Cecil's story has truly touched the hearts of many and has shined a light on the cruel nature of the illegal poaching of animals.