Upgrading your heroes improves their stats but also decrease their deploy cool down and increase their movement speed. There are 30 possible upgrades for each hero.

Leveling up your vessels increase hit points and at some levels the energy cap you start with.

The more energy it costs to deploy a hero in battle, the stronger it is.

As in many games a successful team means balance. Have at least one hero of each class (Balance, Tank, Damage and Runner).

Consider deploying a heroes that take four or five energy. Once they are on the field, they can take out a whole lot of enemies.

Battle in the Arena as much as you can, you'll get off with great rewards. The higher you get better are rewards. Tokens when you win, which can be redeemed for hero DNA or other power-ups.

Complete Daily and Weekly Quests for XP, gems and coins.

Use the Starter Packs from the beginning as they will give you a boost to advance especially early on in the game.