A few concepts I recently did as a test using a library of 2d elements I've built over time. Essentially 2d kit bashing. The goal was about speed, i wanted to see how fast I could develop a design using these elements. Each concept took between 5-15 minutes to produce using the same 2d elements. The guns and jet pack were quick, taking no more than 5 minutes or so, the arm and vehicle took a little longer; around 10-15 mins. It's quite a fun process! like using those colorful bricks as a kid :)
Update - I've recently added a brush set to Gumroad that contains many elements used in creating these concepts. https://gumroad.com/l/ajPj
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