The otherwise excellent tutorial doesnt mention it:

https://adventuron.io/documentation/tutorial-a.html

So I am thinking using something like https://www.pixilart.com/draw

To take it further this is a great use for Text 2 IMG AI models

https://deepai.org/machine-learning-model/text2img

https://vision-explorer.allenai.org/text_to_image_generation

https://creator.nightcafe.studio/create/text-to-image

https://hotpot.ai/art-maker

and then something like this at the end: https://pixel-me.tokyo/en/