Fracture

Even though this isn't as tough as some Hardcore/Insane modes it can be a little frustrating at times.

Act 1 is from Alcatraz (the Tutorial) to the end of Dreadnought Revealed. Most of it is pretty easy, but you will get stuck at a few bits.

Some Tips.
Make sure you carefully work your way through the levels. Use your radar to spot the enemies and clear them, while staying in cover. If you have no cover ... make it by raising the ground (if you can). They don't have infinite respawns, but sometimes there are 2 or 3 waves.

Make good use of the weapons you find along the way. I used the Raptor mainly as it is good for headshots. The Bulldog is also good for close combat as it has rapid fire. Later on you'll get the Invader (shotgun) which can be good, but not too much ammo for it.

Take your time and at some parts of the game you'll find some "Sweet Spots" where you can do alot before entering the battle. A couple of examples are :-

When you restart the conveyors you'll come across a few guys then have to walk around the corner to take out a guy with an Invader. He's a pain, but I found that if you lower the ground between the bollards and the back of the cave you can stand at the back of the hole (looking up the ramp) and he doesn't move.

A little after it you'll enter a room with 3 green doors and you have to enter the middle one. Stay back in the tunnel you enter the room in and let them come to you. Once you've taken out the Hydra's get their weapon and clear out the room.

When you're asked to repair the bridge, don't go down the ramp .. stay at the top. One guy will come up and you need to get rid of him. Once done its easy. There are two Hydra's plus a bunch of others. The Hydra's will bounce about and go to the left on a ledge. They fire at you, but miss everytime. Take them out with head shots as they don't move.

At the Golden Gate bit, where you have to remove the transmitters. Run left and throw a grenade at the 1st transmitter. Then jump over the wall and take out the back left one. Build up a barrier to stop the guns shooting at you and lob a grenade at the 3rd one, before heading into the tube. Once inside pop out and lob one at the last transmitter. I only killed 1 guy in this section.

The last point is that as long as you make it to checkpoints, you don't always have to kill everyone. I did this early on when you get a ride with the dropship across the gap. Once you've cleared out the 1st load your told to go to the elevator. I just ran and used the ground raising to build a barrier between me and them and got the checkpoint in seconds.

Have Fun