Keep moving. That’s typically good advice in any top-down arena-based game, but it’s absolutely vital here since you have no direct means of defense.
Know where the mines are. It’s important to know where you’re leading the giant pack of killer baddies. If there’s no mine ahead, there’s no relief ahead. Always have the next mine in mind.
Use the Meltdown. It’s easy to forget about this ability, but it’s absolutely vital for taking your scores to the next level. If you’re in a pinch, slow things down and use the extra speed to get away.
Save your Supernovas. After you create a Supernova item, it will remain on the field for quite a while until you detonate it. It’s best to use it when you’ve got a big crowd on your tail.
Chain those explosions. Get a nice bunch of mines and Supernova items near one another and you can create blasts that will cover almost the entire field. Imagine how many points you’ll earn!
Master the two different ways to detonate a mine. You can immediately explode one by touching it with your fireball, or you can explode it on a delay by moving in its vicinity without directly touching it. The former can help in a pinch, but the latter usually takes out more enemies.
Learn the different kinds of enemy behaviors. There are several different enemy types, and you need to know what they can do if you hope to survive. Make note of new enemies and study their habits.