Perform Perfect Reloads as often as you can as they quickly top off your ammunition and they factor into your Star rating at the end of each Chapter.
Unlike in Dead Space 1, Stasis energy recharges automatically. This means you don't have to worry about Stasis Packs or Recharge Stations, though in rare cases you can find items which instantly refill your three Stasis charges.
Weapon and R.I.G. Upgrades return, but they are not applied via a Bench. Instead, Weapon Upgrades appear as collectibles and R.I.G. Upgrades are awarded when a certain cumulative number of Stars are obtained. Additionally, you don't have to worry about Power Nodes.
Glow Worms can be recharged before they start dimming.
Many enemies from Dead Space 1 return in Dead Space: Extraction, and the same general strategies for defeating them still apply. Exceptions to this include the Brute and the Lurker. The Brute remains similar, but you can no longer cut off its legs. The Lurker, however, functions very differently. Instead of whipping barbs at you in a straight line, Lurkers now launch slow-moving explosive barbs (like rocket-propelled grenades) that can be grabbed and thrown back with Kinesis.
Swarmers (the little Necromorphs released from Pregnants) do noticeably less damage (even on the Impossible difficulty setting) though they can take longer to shake off.
Instead of clumsily swinging your currently held weapon, you now quickly swing a Rock Saw for melee attacks.
Most of the returning weapons function identically or at least similarly to their Dead Space 1 counterparts. Two notable exceptions include the Flamethrower and the Ripper. The Flamethrower is now more powerful and can work in the vacuum of space while the Ripper is slightly more complex to control but also more versatile.
In Dead Space 1, the Plasma Cutter was your bread-and-butter weapon. In Dead Space: Extraction, the Rivet Gun serves that purpose as you always carry it and have infinite ammunition for it. However, it has a slow firing rate and is fairly weak.
The Line Gun is still great for cutting all three tentacles off of a Lurker. Additionally, a single Line Gun bolt can dismember a Slasher's arms and legs with one round if they are crouching.
If you are using the Ripper on a Slasher, it is easier to dismember their legs and then aim for their arms. Slashers instantly die once their arms are removed, but it can be difficult to remove their arms with a Ripper blade without unnecessarily wasting ammunition.