Big Mick's Outback Laundry - https://www.artstation.com/artwork/Jvkz4v
Flyin' Vikings - https://www.artstation.com/artwork/m8ldV
I didn't create anything for my day one other than code, and from memory I didn't do any art for Stacker... oh wait, I did the flipbook sprites for the water but that's not going on artstation :D I did a ton of sprites for octalien but it hit day6 so it doesn't count here.