As mentioned, Mayday appears in only a single episode of "The Bad Batch" titled "The Outpost," which saw another clone named CT-9904 or "Crosshair" (the only member of the Bad Batch who joined the Empire, also voiced by Dee Bradley Baker) visiting Barton IV to reinforce Mayday's squad — which was down to just three troopers after a year on the planet.
We learn that Mayday cares so deeply for his fellow troopers that he's kept the helmets of all his deceased comrades. Later in the episode, the bearded commander expresses his distaste with how the Galactic Empire uses the clones as expendable, unimportant cannon fodder. These displays of affection and loyalty toward his fellow soldiers are part of why the charismatic Mayday managed to live on as a popular character within the fandom, despite the fact that he dies later that same episode.
After an avalanche leaves Mayday on the verge of death, Crosshair fights his way back to the Imperial depot in order to save him — only for Imperial Lieutenant Nolan (Crispin Freeman) to deny him any medical aid, believing it a waste to expend such materials on a replaceable clone. Although fans may have wished for this disillusioned clone commander to last a little longer, Mayday still gets the last laugh in the end when Crosshair executes Nolan before dozens of witnesses — allowing Mayday's small appearance to have a major impact on the rest of the story.