Towards the end of of the quest Baxter's Propaganda, you'll meet with Skinny, who has a proposition for you. You can either rat him out to Wulf, or go along with him.
If you want to relive the fun of the Claws from shards I, go along with Skinny.
Take Skinny's key and work your way around to the east side of the Upper District to find the secret entrance to the back of the armourer's house and open it.
If you want to do it quietly, do it after midnight when the armourer is asleep. You should have no trouble sneaking past him in bed. If you want to loot the rest of his house, just do it quietly, though, unless you have two points in hacking, you won't be able to hack his safe (4-6-3-2), so mark it for later. If you do it by day, there's really no point in sneaking, as I found he always spotted me anyway, so dash straight forward and grab the signet ring that's beside the goblet on the small stand, run back out while the guy is threatening you, and don't forget to lock the door behind you. Although you're going to return the key to Skinny, you'll still have access to the armourer's secret back door (maybe you made a copy of the key).
Go back to see Skinny and (as long as you did remember to lock the door behind you) he'll lead you to a trap door hidden in the bushes just outside the World-Heart dome on the north-west edge.
He'll open the trapdoor for you and then leave telling you not to forget to close it again when you leave, though there is no penalty for not closing it.
You can climb down the two ladders or just drop down, using your jet-pack to break your fall, which is much quicker.
You'll find your old colleague Yasma. Tell her the Berserkers sent you for the best reaction. She'll take the signet ring and give you some propaganda leaflets you are to use to fool Wulf into thinking he has done his job.
Head back up, using the ladders or your jet-pack if you're handy enough with it, and go south through the dome to Chloe's bar and lie to Wulf about where you found the leaflets for a Destruction quotient decrease, 500 shards, and the end of the "Baxter's Propaganda" quest.
You can go back and start working on the Claws' questline right away, or leave it until later; it's entirely up to you. The quests shouldn't involve any fighting unless you really screw up, and they aren't that hard if you can pick locks and hack electronic safes, and you can pick up some good experience so doing them early on is fine.
I recommend doing them solo, purely on role-playing grounds. If you take Caja with you into the Claws' lair, there's a bit of dialogue between her and Yasma, but never have I had a companion react, positively or negatively, to anything I've done for the Claws.
When you go back to see Yasma there's a conversation covering a lot of backstory, and she gives you your very own Claw, inducting you into the gang.
Like the last time, there's an assignment chest and a reward chest, and the Fort is littered with dustbin-style dead-drop boxes which are to be used for turning in all the loot except for that from the final mission.
The first mission is to steal some fertilizer from the chest in Thorhild's hut out where they cultivate the seedlings. There's a key to it in the hut, but it's almost impossible to find unless you have a pair of "Perspective" sunglasses, end even then you have to think to look *up* not down. It's on the ceiling in the middle of the hut. The order for the pins is 4-5-3-2-6-7-1-8, then pull your lockpick all the way back out of the lock to spin it open.
Drop the loot off in one of the yellow-marked dead-drop bins (there's one conveniently near the Fort teleport) and head back to Yasma. Pick up your reward (150 shards) from the reward chest and your next two missions from the assignment chest.
This one is really easy if you've already talked to Tilas. Sleep in the Claws' lair until midnight, then walk over to Tilas' place. He should be asleep in his bed, so sneak in and crack his safe just to the left of his front door (the code is 0-0-0-0) for his book on distilling. There's also an unlocked chest if you climb the ladder to the little loft.
If you drop this off and go and collect the reward, it's only 50 shards, but, as it's still dark out, I suggest you just go on to the other mission you have.
This mission is best done after you've solved Scrappy's gas problem and got him back to the mine.
If you have access to the upper lever of the Fort, head to the Duke's Bunker teleport, walk west, and jump off into the ravine. As you descend, you'll see a campfire. Try and land beside it. Then if you walk directly north-east, you'll find Scrappy's chest key on a small table in a shed. If you don't have access, you can either wait until you do, or just walk around the long way.
If you are collecting locks for the Key Master achievement, don't pick up the key. but head south from the campfire and turn left into Scrappy's hut where the chest is against the back wall. The pin-order is 5-6-4-3-2-1.
If you didn't collect on Tilas' book already, you have Scrappy's figurine, Tilas' book, and no more missions, so head back to the Fort teleport, drop off both bits of loot, and go back to the Claws' lair. Your reward for Scrappy's little figurine should amount to 400 shards.
Assuming you've already talked to Fenris, he should be standing outside his front door. If he's sitting inside, just have a word with him and he'll move outside. It's pretty easy just to stand behind him, crouch down, and slip in the door behind him, but quick-save in case he spots you and you have to reload/repeat. His safe is to the right against the back wall and the code is 8-6-9-6.
With Fenris' criminal records in hand, find another dead-drop (there's one just to the north-east of Fenris' front door), dispose of your loot, and head back to pick up another 500 shards from the reward chest, though you will find the assignment chest is now empty.
Have a chat with Yasma for some more backstory. If she tells you there are still jobs that need doing, it means you forgot to drop off the last loot in a dead-drop, otherwise she'll give you one last mission. The target? RAT! For this you will need to have obtained access to the upper level of the fort by winning over one of Thorhild, Tilas, or Scrappy as your advocate; getting this far into the Claws questline means you've already completed the quest Baxter's Propaganda.
For this, you really do need lock-picking 2. If you're doing it my way, it's still dark, though I don't think the time of day really matters here, despite what you are told. If you haven't progressed very far amd Rat is sitting on his throne, you should do a couple more things (A Thief for Halvar works well) until Rat is at the foot of the steps and talking to someone so you can just walk up the steps behind him, to the chest to the right of his throne, and pick the lock on the safe. Don't try sneaking, or someone will notice and mayhem will ensue. Just act casual, whistle a popular show tune, and pick the lock (5-4-6-7-8-9-3-10-2-1) as if you were watering the plants. Take the loot, especially one of Rat's "blood pacts".
Finally, walk, (don't sneak) over to the top of the stairs and take one single step down. Pause. Take a step. Pause. Take a step. Pause. Keep this rhythm up until you're half-way down the stairs, whereupon you can jog down and turn right and head over to the safe to the right of Rat's bed. No need to be sneaky. If you have two points in Hack you can hack the safe, otherwise it's 4-7-8-1, and you'll get the second of the "blood pacts".
Better safe than sorry, just teleport from the cellar to the Fort teleport and jog back to the Claws' hideout.
Yasma is amazed. You get 1,000 shards and 4,000 XP, and th...th...th...that's all, folks.
But wait! There's more! Well, there's more if you decide to join the Berserkers.
When you're still a lowly Cultivator you can go and see Yasma and tell her you're infiltrating the Berserkers, but when she learns you're just a Cultivator, she tells you to come back when you're a Warrior.
Once you're a Warrior you have a choice; you can do Rat's loyalty test and become a Paladin at level 30, or you can take the Claws' route and, optionally, end up as an Outlaw, but you'll close off the option of becoming a Paladin.
When you are looking to be promoted to Paladin, Rat says you can skip all the usual tests if you do him a favour. He knows the Claws were behind the propaganda leaflets and believes they were behind the bombing as well. He wants to ensure they will never be a threat to him again, so he wants you to steal Hector's Book of Claws, containing information on all the members.
Go to the Crater and (if necessary) pay Xander 50 shards to let you into the upper district. You can talk to Hector if you wish, but you have no opportunity to rat out Rat and tell Hector what you are here to do. All you can do is walk up the stairs, open his chest, and take the book.
Doing this is the only way you'll get to become a Paladin.
Return to Rat, give him the book, and, when you're level 30, he'll promote you to Paladin. If you return to the Claws' lair after this, you'll find it empty, and you can loot Skinny's and Yasma's chests, though they contain nothing of any worth. The reward chest does, however, contain a note saying the Claws have been betrayed but will never die. "We will meet at the stone under which the screamer flies". If this location exists in Elex ii, I have yet to find it.
If you go and see Yasma when you are a Warrior, she will caution you not to agree to do any favours for Rat, as they will surely harm the Claws. She has a job for you: stealing the guards' rotation schedule. This begins the quest A Mole for Yasma.
If you did Halvar's thieving job already, you'll know the ground. Even though you're told to do it at night, it really doesn't matter. Walk into the day guards' ground floor sleeping quarters (behind Halla) and go into a crouch, hack the safe (9-8-1-3), grab the document, and return to Yasma.
Yasma tells you to take the schedule to Hector, who will then make you an Outlaw. You can ask her, "What if I don't want to be an Outlaw?", and she'll say, "Then don't be an Outlaw", but you'll still need to take the schedule to Hector.
On one occasion I encountered a bug here; I told Xander I was on an errand to Hector for Yasma and he told me I could go on up, but then he made me give him another 50 shards anyway. The next time I did this, it worked just fine. After talking to Hector you can no longer become a Paladin; he'll offer to let you join the Outlaws, and, if you're level 30, you can.
If you do this and then go to see Rat, he'll tell you all promotions are on hold indefinitely, so raising you to Paladin is off.
If you have Hector make you an Outlaw Captain and then go and see Yasma, she'll give you 300 shards, but she has no more work for you and it's finally over.