The Battle Cats

You have to repeat levels in order to get EXP in order to upgrade units.

You have an energy bar which puts an arbitrary cap on how many levels you can play in one session.

You can use the game's premium currency to instantly refill your energy.

After completing a level, you have a random chance of getting a treasure that will boost your performance in future levels.

There are a few events that occur at extremely inconvenient times for example: a level that only appears at 2:22pm on the 2nd and 22nd of the month for only 2 minutes. Beating this level gets you one of the strongest characters in the game.

You get loot box tickets and often other rewards daily.

Grind for XP to level up units.

It’s called cat food and it’s very expensive. But there are events that give out large amounts which helps. Cat food is not ever required to win. You can use cat food to do many of the dark patterns listed in this category. But some categories specify “advantage against other players”. There is no competitive play.

Regular events with units that never return. Forces you to spend time trying to get them and these are often obtained with premium loot box style methods.

Aside from the common “wait for energy to recover” there are also a few others. This seems to be a recent thing and it’s only for bonus levels that you can randomly unlock and take time to “discover” afterwards. These levels aren’t actually important so it’s not a huge issue. Main gameplay isn’t impacted by this.