2 months ago I have decided that I will start participating in The Gnomon Workshop 2D Image challenges, where each month is given topic and first 4 winning designs are rewarded with educational content from industry professionals. Last month I have won 3rd place with my Street Patrol design, but this month I have managed to win 2nd place with my Gigant Mist Walker concept. I strongly recommend participating in this challenges even if you are just starting out, since idea is what matters and not highly polished artwork.
Here is link to 2D Image challenge forum: http://forums.thegnomonworkshop.com/forumdisplay.php?f=2
For Mist Walker challenge I had to imagine a character or creature that appears when the fog rolls in. I did around 15 thumbnails of possible creature designs, from which I have selected best and did another 4 thumbnails of different environments and compositions. Each thumbnail took me around 10 minutes and they were done in black and white. After that I have started colourizing them and adding details as it is showed in attached gif image.
I encourage you to give it a try and even if you don’t win, you will definitely improve as an artis and designer. Good luck to you all!