Heyho, GreenGiraffe!
Thank you, glad you like the style!
You mean what art tool I use? I mostly use Photoshop because it's good for almost all purposes (character art, background art, UI, logos, fonts etc.) and lately I've started inking with Procreate (the characters in Monster Mawl are all inked like that).
Generally, I love to try out new tools, but it's a good idea to stick to the ones you're most comfortable with :)
Hope that helps!
Take care and stay funky,
Dez