Here are some things I’ve discovered as I played Oz: Broken Kingdom.
Ability Leveling. Ability cards are leveled up by acquiring duplicates of an ability and then upgraded using essences. To obtain ability cards, you can play specific stages, purchase from item shop, or acquired through the pool of wonders.
Stage Drops. Each stage states tells you what ability you can obtain, along with additional materials for gems or character evolution. It’s also noted that you may only acquire an ability from a stage once a day as acquiring an ability enables a button that allows you to refresh the skill by spending some emeralds. This does not apply to stage drops however, as ores can still be obtained.
Shop Keep got you covered. Ability cards can also be obtained by purchasing them through the item shop with essence. Available abilities in the shop will display a tag in your abilities menu. The abilities and items will change after an extended period of time, refreshing after a couple of hours. As of right now, there is no limit on how many cards you can purchase besides how much essence you want to spend.
Wonder what you’ll get? Abilities can also be obtained by using coins at the pool of wonders. Coins can be purchased through varying amounts of emeralds and a free bronze and silver coin given out daily. You can additionally purchase coins for a specific character to obtain abilities for that specific character.
Completion-ist. Completing 3 stages with 3 stars allows you to raid the stage, which allows you to get the stage rewards without playing the stage, at the cost of the usual energy amount. To get better ratings in a stage, take as little damage as you can. I was able to complete a stage with very low health and managed to obtain a 1 star rating.
Mighty Tin Man is MIGHTY! To increase the might of your characters, upgrade their abilities and rank up. Upgrading abilities increases the total might and ranking up gives a boost to all your characters. Ranking up can be achieved by various means like doing quests and playing levels, so best bet would be to play the game as you normally would.
Try things out on an emulator! Oz: Broken Kingdom can be a bit graphic intensive so it wouldn’t hurt to try it out on an emulator. I would recommend Leapdroid as I’ve been using Leapdroid for some time now. Do note, I have experienced an occasional lag on Leapdroid 1.6 for one reason or another, but aside from that, works very well. Playing Oz on a larger screen could also help as having a larger screen allows you to see more details you otherwise might have missed on a mobile device. Consider giving it a shot!
If I can come up with more tips, I’ll update this article. Hope these observations helps!