10) Make smart use of World Crystals.
Every one of your creatures can equip a world crystal, which adds one buff to them either permanently or until it is replaced with another world crystal. You get a new one each time you beat a boss, whether they are a new boss or an old boss. Make sure that your entire active party is equipped with only the best world crystals.
9) Go back and play old missions as often as you want to.
You will lose progress in your current mission if you are currently playing one, but old missions are a great way to farm for ether and creatures. Simply tap and hold on one of the spots you’ve already beaten on the world map (darkened spot) to re-enter it. Enter and beat the quests, rinse, lather and repeat.
8) Keep an eye on how many lives (hearts) you have.
If you lose all three of your hearts, you’ll lose the stage and you will be force to start right back over from the beginning. You will lose one life if you lose a battle, or if you blow the mission requirements and spend all of your allotted moves without completing all of the required quests.
7) Purchase the Rune of Birth to increase your likelihood of finding new creatures.
When you buy a Rune of Birth from the consumable store, it activates automatically, and if you own multiples, they will all activate automatically, one at a time for one day at a time. The price goes up as you purchase more, then goes down as the time passes (about a day or two later the price goes back down). They will make more creatures pop up on the map as a reward for quest completion.
6) Play the event missions for huge rewards.
These are limited edition missions that pop up whenever the developer feels like putting them in the game, and they will earn you a huge amount of ether and creatures for completing them, but they will be very tough to beat. Make sure that you are ready for them before you try to play them or you will end up wasting a whole lot of time since you can’t keep matter, ether or creatures when you lose.