Astrael
Member
These enemy and character graphics were most likely drawn digitally using a Wacom (or Wacom-like) tablet pen or tablet PC like the Surface/iPad Pro from line art to color. You'll draw lines and colors on a transparent layer (not on the background/paper layer) so that you can hide the paper/background layer when you want to save the final image. It saves a ton of time to do it this way, since you can draw directly inside the program (Clip Studio / Photoshop / whatever) you end up painting in. The only important thing is being able to save your final image into a transparency-supporting file format, usually .png for higher color depth images like these. Your original drawing doesn't have to match the resolution of the target size - this is the only real difference from retro pixelart workflow where maintaining pixel-accurate color and lines is important; it's much better to draw a much larger resolution and then save a reduced copy of the image file to match your target on-screen size based on your engine.
Optionally, you can choose to draw line art traditionally in a sketchbook, then scan the drawing, and use Photoshop or whatever program you're using to clean up and sharpen the lines and then digitally paint over the rough/ink. Or, you could do the entire painting traditionally, scan and just use image correction with a little digital manipulation to touch up blemishes or fix lines/blends. Or whatever medium the artist like working in. This takes more work since you have to cut the enemy/character drawings away from the paper background so it can be re-positioned, and not have it look too matted when drawn over your background in-game.
The final option (off the top of my head) is in fact to use a pixel art program. You'll just end up using far more colors than a retro sprite would, but since all images on a screen are just pixels, you could reproduce any image you see on a monitor if you were dedicated enough, no matter how big and complex the art. This is ultimately a variant of the digital drawing method, but more focused and time consuming for larger image sizes.
Basically, all that matters is getting your drawing/painting into your final .png image asset. How you get there is up to the artistic direction of the graphics and artist's preference. (Sorry for the long reply I tend to ramble)
