Resources

You'll need rare resources for researching upgrades. Iridium, Palladium, and Platinum can be found on most planets. Element Zero (aka "eezo") can only be found on about 10% of the planets, including many of the planets involved in assignments (meaning you won't really need to search for them; you'll find them by following objectives).

Some planets with Element Zero include 2175 Aiea (Alpha Draconis / Rosetta Nebula), Caleston (Balor / Caleston Rift), Daratar (Faryar / Hourglass Nebula), Eingana (Amada / Omega Nebula), Erinle (Osun / Hourglass Nebula), Joab (Enoch / Rosetta Nebula), Laban (Enoch / Rosetta Nebula), Mizraim (Enoch / Rosetta Nebula), Sanctum (Decoris / Sigurd's Cradle), and Watson (Skepsis / Sigurd's Cradle).

Iridium is used to research heavy weapons, submachine guns, and assault rifles. Platinum is used to research sniper rifles, shotguns, and medical equipment. Palladium is used to research heavy pistols, armor, and cybernetics. Element Zero is used to research biotic powers and tech powers.

Planets are rated as "rich," "good," "moderate," "poor," or "depleted." This rating will change as you mine resources from the planet. You'll be able to mine way more resources than you'll ever need, so don't feel obligated to mine each planet to "depleted."

You'll need to purchase probes (from fuel depots) to mine planets. Once you've found a good resource spot on a planet, launching a probe will gather the resources for you. Probes are cheap (only 20 credits each), so keep your ship well supplied.

Early in the game you'll get an upgrade that will make scanning planets easier. So don't bother doing a lot of scanning and mining before that.


Crewmates

Including DLCs, you'll be able to recruit up to eleven crewmates to help you in your missions.

Each crewmate will start out a little leery of you, but completing a loyalty mission for them will change their tune. You won't have to worry about gaining approval or influence. Completing a crewmate's loyalty mission will also allow you to change the appearance of a crewmate and unlock a power for the crewmate.

Each time you complete a loyalty mission, you'll also gain a potential new power (you'll be able to train one power from the list available from all of your loyal crewmates).

You'll have to take two crewmates with you for every mission.

Crewmates you don't use will gain as much experience as the crewmates you do use, so you're free to mix and match your crewmates, and "tune" your party for each mission.

The more loyal crewmates you have, the better you'll be able to survive in the game's final mission.


Ammunition

Unlike Mass Effect, you won't have to worry about your weapons overheating. But you will have to supply them with bullets.

All regular weapons use the same bullets. When you step on an ammunition clip, you'll gain bullets for all of these weapons. Heavy weapons use a special ammunition that you can only replenish via power cells.

When you click on power cells, not only will you receive some heavy weapon ammunition, you'll also completely restock the ammunition for your regular weapons. Using a weapons locker (even if you don't change your weapons) will also restock your ammunition.