Clash Mini Seasons
Yes! Like many games, Clash Mini also has a Season Pass, called a "Season Road". The Season Road helps give you incentive to play consistently to progress up a road and unlock rewards along the way. While it is optional to participate in the Season Road, you will miss out on rewards by ignoring is, so be sure to check the road regularly to claim things you've unlocked.
Clash Mini also offers a premium version of the Season Road with the purchase of a "Mini Pass". This pass lets you unlock extra exclusive rewards along the Season Road in addition to the ones you'd unlock for free. The extra chests can help you level up your units quicker as well as unlock some cool looking outfits for certain units.
To level up on the Season Road, you need to collect Carrots. These carrots are rewarded from completing Daily Quests and Mini Quests. You can do up to 6 Daily Quests per day. Mini Quests are finite, but there are a decent number of carrots to be earned from them still.