Mission: Build a 2 star 5 cost unit

Getting to a high level before anyone else is important for getting a 2*r5

Learn2Econ

Spamming games

You have to have a game go real late since you'll need lv8-9 most likely to have the RNG to get it, so you have to have good hp, survive, and econ. That and you have to do it without stomping your enemies too hard to where you win with a 5 cost with no extra stars.