It’s Ambulocetus natans, folks. They could move around on land using contraptions called “legs” – as you may have noticed, modern whales typically don’t have these. Known from a single fossil found in Pakistan, they existed 48-47 million years ago and then literally disappeared into thin air (confirmed by witnesses at the scene)
A mammalian crocodile. Ah, Paleogene, how I miss thee
Interestingly, there was also a crocodyliform Pakasuchus (“cat crocodile”) with mammalian characteristics
Live and learn. Thank you for this new knowledge!