Crystals, Moonstones, Raretarium
 Crystals, Moonstones, Raretarium
One of the bonus' of the game is that you have some things to do besides the actual storyline missions. These include collecting crystals in the Tabora desert, finding moonstones in the ice fields of Grelbin, and mining for raretarium in the Tabora desert sands and the Grelbin ice fields.
The first thing you will notice about planet Tabora is that it has a huge desert area you can explore. In the desert is various little enemies, many sand hills, crystals, and large beasts hidden in the sand. One of the perks of collecting all the crystals in the desert is that you can trade them for lots of bolts. Most of the crystals you can get by just running around the desert and freeing them from their little cages. Some you might have to fight off some enemies before you can get them safely, and some are guarded by large beasts hidden in the sand. When you near their crystal, they rise from the sand and shoot a lightning stream at you. They require a few shots from a powerful weapon to be defeated, and when they are defeated they drop a crystal. If you do not feel like running around the desert for hours trying to find all the crystals, wait until you get the Charge Boots. You can zoom around the desert and collect the crystals pretty fast.
Another thing to do in the desert is collect all the raretarium hidden beneath the sand. You do this by driving the mining vehicle around and drilling it up. To get to the vehicle, which is near the start of the level, you need to have the Magnet Boots which you get a few planets later. Once you have the boots, you can walk up the magnet path along the side of a structure to the mining vehicle at the top. When in the vehicle, you can then drive around the desert digging up the raretarium, which can be used to purchase upgrades for your spaceship. But one of the downsides of the vehicle is that if enough enemies attack you, the ship will explode and you will be stranded. If your ship does happen to explode, it will respawn all the way back where you got it, which can be a pain. One way to make your ship not explode is to get out of it when you near enemies, and kill them all, so they do not attack the ship.
On the 2nd last planet of the game, Grelbin, you have another opportunit to collect things and trade them for lots of money. The snowy planet features a large ice field, which has many snow hills and ice structures throughout. To access the large part of the ice field, you must first collect a few crystals in the small field area near your ship. Once you collect them and bring them back to the man, he makes some bridges appear, which allow you to access the larger ice field area. Throughout the ice fields are tons of Yeti's, which are very strong, and also some gigantic ice dragons that hide in mounds of ice. If you happen to be caught off guard by one, it will blast you with a powerful ice beam that takes a lot of your health. They take a lot of powerful weapon shots to be taken down, but like the sand beasts of Tabora, when you defeat one they drop (in this case) a moonstone.
Throughout the desert will be moonstones in cages. They will take a few shots to destroy and collect, so watch out for the Yeti's and ice dragons in the surrounding area. Like the crystals, there are many to collect. Most are scattered through the fields, and the rest are collecting by killing all the ice dragons. If you collect them all and trade them, you will get tons of money.
Like the Tabora deserts, there is also some mining to do. You unlock the mining vehicle by going through the factory area and finding Angela. Once you get to the vehicle, it will spawn near Angela's home on the planet. Like on Tabora, the mining vehicle can be used to dig up raretarium on the planet. But like the Tabora mining vehicle, it explodes pretty easily. One ice dragon blast will destroy it, so make sure you do not stay near their areas long. It does however take lots of Yeti shots to destroy it, which means you can zoom around the ice fields ramming Yeti's to death for awhile.