Mr. Sneezums is a Smilodon and a former anachronism in the timeline.
Due to the meddling of the Legends in the timeline, Mr. Sneezums was catapulted forwards in time to the year 1870, where he was captured and sold to P.T. Barnum to be featured as the latest attraction in his Roving Museum of Freaks and Hypnotic Hippodrome. Barnum hoped that Mr. Sneezums would draw huge crowds to make up for the cost of purchasing and caring for him, as well as to raise the funds to keep running the circus. However, when the Legends arrived to correct the anachronism, Nate Heywood and Ray Palmer accidentally released Mr. Sneezums from his enclosure and drastically increased his size, which allowed him to escape into the woods nearby. He was eventually tracked down by Sara Lance and Amaya Jiwe, who were able to shrink him to a more manageable size and bring him aboard the Waverider, where he was locked in a cage until he could be properly returned to his own time period. Later, Mick Rory opened the cage to feed Mr. Sneezums some meat from his sandwich, but the tiger used this opportunity to once again escape confinement and managed to evade capture aboard the ship. He eventually returned to his normal size in front of Sara and a startled Ava Sharpe, but he was once again subdued before he could harm anyone. Afterwards, Ray gave him the name Mr. Sneezums due to his own cat allergy.