Ability tree
There are three areas, ATK, DEF and General, in the ability tree. Better boosts can be accessed by using your Ability points in the same branch. If the result is not what you expected you can reset of all Ability points. The first reset is free, but subsequent ones require payment in gold.
Equipment
Spend silver to enhance your equipment to improve your basic stats. To get started, tap the "Enhance" button at the bottom. You can select five of the six slots before you must wait for the cooldown timer to finish. The Mine is another way to make your gear better. You can spend silver to dig for gems that be inlaid into your weapons and armor. These work together with enhancement. The higher the level of your gear, the more gem can be inlaid.
Training
Training your character and pet can improve all of their basic attributes at the same time. However sometimes it will only increase two of them at the expense of the third. If you have enough gold, spend it to train, which increases the chances that all stats will be boosted.