Veequitto

This is before I leveled up⬆️

This is after using up all my grimms and devil points to level up and unlock skill level.

you can still win battles if your team's strength is below your opponent's. I'm not 100% sure anymore, but I think being 80k below is still doable tho it might take a couple of tries to win sometimes

if your opponents have a skill that can stun you (paralyze, curse of the zombie, curse of the frog, scarecrow, confusion, stun or sleep) I'd opt for a 50k difference

getting hit with berserker is actually kinda useful bc it doesn't disable your special skill and increases your charm; it's only midly annoying when you try to time all your skills but other than that it plays into your hands

prioritize being able to use each one of your skills twice per battle (four times in boss battles) over using them at the same time as your opponent

buy the flash sales you get after losing a battle to get more rainbow glowsticks. Those cost 20 Devil Points so you can buy one almost daily if you do your daily missions

if you're about to lose a battle, you can fully close the game and open it back up again to restart the battle without losing your AP. Just make sure to do so before the loading symbol shows up, otherwise the game saves your defeat

you also can sometimes get fever time if you restart battles with the above method, so it's worth a few tries

if you don't have any UR/UR+ cards for a specific sin, SSR cards on level 80 can also help out a lot

make sure to NOT grind for Grimm in season 1. A 3-star stage from season 2 onward gives you about 500 Grimm per sweep, in season 1 it's only about 200 or so