Minion Masters

This achievement was not popping in build 1.3/early 1.4 but it seems to be up and running again (as of late June 2019)

Daily Quests can be found within your profile (bottom right of the main menu) but will show in top right corner when ready to be claimed.

You can have up to three quests live at any point and these don't have to be completed within one day - once completed a new one won't be offered until the next daily reset (1am BST).

For quests that say something like 'complete three matches with different free masters' - you don't need to win a match but the match does need to be ranked - games that are from the solo challenge line, or the gatekeepers in expedition mode won't count. Free masters rotate once a week but unless the quest specifies different masters, you can use any free master (two available per week). IF the quests asks for a number of spell cards/buildings to be used, these don't have to be different cards and can be over more than one match. Matches that you need to win also have be ranked (non-gatekeeper matches in expedition, conquest, draft, team battles also count here)

Once you complete enough quests, do remember that you need to claim the achievement from the achievements menu (one of the tabs on the profile page to the right, or accessible also from the main menu)

Hope this helps!