Welcome to part two of the guide for how to win in Brave Frontier without spending any real-life money! Click here to go back to part one of the guide.
Another easy way to blow all of your gems is to become impatient and spend them on getting your energy back. However, instead of doing that, regain your energy by earning enough EXP for a level up. The quests provide a decent amount of EXP – however, the Vortex Gates provide a HUGE amount of EXP – even the Vortex Gate levels that you have already beaten before. Go back to them, win, and you’ll likely earn enough for a level up if your exp bar is anywhere near halfway full.
This is true for all of the Vortex Gates, but one of the daily gates – the Friday one, is especially good for earning EXP, as that is the main point of the Friday gate (besides earning crafting materials). Any of the other ones, though, even the daily gates which don’t specialize in gaining EXP, will level you up quickly, allowing for quick energy refills.
Beyond that, though, when you run out of energy, use that time to do something else. Go to your town and spend your Karma on upgrading things. Go to the Arena and use your Arena Orbs to battle in an attempt to increase your rank. Leveling up will restore your Arena Orbs fully.
Gems can be used to increase your item or unit capacity, but that is generally unnecessary. Fuse or sell the units that you don’t need – there’s no reason to keep around 50 units (which is the maximum number that you can carry without purchasing an increased maximum. Nor is there a general need to have 100 different types of items (or even a possibility of it, unless you’re really trying).
Gems are used to purchase rare summons as well. This is arguably the only worthwhile thing that they are used for. Five gems apiece will do it, and you can earn more than enough free gems from such things as winning a quest area, ranking up in the Arena, or the developers giving away free prizes as compensation for server issues, that you should be able to fill up your entire active battle squad in no time.