Pokémon Masters

Most of the best units in the game are or have been available only once

Units will only have all their abilities if you obtain at least 3 copies of them

Older units are almost completely useless

Some of the worst gacha banners and rates I've ever experienced. The only units worth pulling/releasing are 5* (the highest rarity) 95% of the time. Even if a unit isn't very good, it will still be a 5*. Despite this 3* and 4* units still flood the available units with much much higher rates despite having no value beyond rare, niche support to much better 5* units.

Its pokemon

Most of the best units in the game are or have been available only once. Not only that, but if multiple new units are released alongside each other, and they always are, the new units will not be available in the same banner. So you if you want them, you need to get lucky enough to pull them, sometimes multiple if you want them to be full power, and still have enough currency to make and attempt for the other units

energy purchase

gems, esp. the paid/non-paid gems system

Maxing out a Sync Pairs star count gives you an alternative skin for most 5 star pairs that you can display. Additionally, regular events have badges you can disply on your profile earned by completing missions.

Standard log-in bonuses are administered on a weekly basis, in addition to additional event log-in bonuses.