Fifeldor: Prepare to teach it to me.
Actually, my first advice would be to play the Tutorial (which you start by creating a game on LOCAL), followed by immediately switching to RANKED (TrendyeNt) online mode.
If you want to have an easy time, choose an Apprentice and focus on TOWER Attack (3), Speed (2), Health (2), meaning that each three points in Attack should see two in Speed.
Then start playing through the campaign on Medium.
Ah, sorry, I didn't express myself properly. Due to my lack on skill on that sector, I can not guestimate the amount of work and time that a professional artist would have to dedicate for a given task, simply because I have nothing to compare with.