Hey uhh I know I haven't responded to your previous post yet but uhhh

Where are you currently in arknights? I am curious on it.

Still at 4-7, I think I'm stagnating. Lowkey I'm thinking of what I want outta this game, and what I want is its world and story.

Soo uhhh do you think the anime is a good place in for up to episode 6?

Nah, some of these levels can be pretty dang hard, especially with different rosters and all that. Plus for you it feels like you have 2 limiters:
1) Your obsession with replicating canon (lol)
2) You not enjoying gameplay all that much either, from what I can tell?

The anime's Season 1 goes from chapters 0 to 3 I think, but I'm pretty sure you'd need episode 6 at least to watch through Season 2

Lemme see if I can come up with a more general way of going about the level and I'll get back to you with the steps lol (it feels like it's a matter of understanding the space and order ngl. I keep on bullcrapping my way through but what I'm doing is not exactly a shareable strat xD)

-Galaxian-

'Kay, but the offer's always open in case guides don't solve any problems you may be experiencing at the roots. Personally I try not to look at any guides for the games I play and prefer to watch different people going through different levels, but you probably have a different way of learning than I do (also full disclosure: I probably need to start doing that soon for Arknights lol, I feel like I might get bottlenecked)

-Galaxian-

Yeah, I learned I suck at geometry (spatial imagination) and that I hecking love narrow alleyways

In seriousness I wouldn't say I learned more on tower defence as a genre or concept xD 'cause usually if I learn more on a broader topic, I can summarise big ideas, but I don't seem to be able to do that for Arknights :] like I could talk about deployment, positioning, and splitting the army and stuff but that feels like the most basic stuff ever lol

-Galaxian-

I'm gonna assume that you might be being too hard on yourself and assessing yourself as lacking in more fundamentals than you actually do. For instance, I feel like I struggle with a few keypoints, which makes some levels super hard for me, but crashing and failing a few times on the same level makes it feel like I just suck in general xD
I did end up redoing 4-7 for you. I thought I'd analyze my thought process on it regarding the fundamental stuff in it to see if we can come up with a way to get us out of our ruts, 'cause I realized redoing that level specifically that I apparently am pretty good at improvising, so much so that every time I redid it I was doing something different lol. That results in the weakness of being easily plowed over in higher-difficulty content, where redeploying might fail. Or simply auto might fail due to the details being minute

My squad:
-1 AOE Archer (Sesa, Skill 2--should be replaceable with Catapult)
-2 Vanguard:
-> Auto DP gen: Fang (I used her because she's of a lower level and so theoretically should be more duplicable)
-> DP gain by defeat basis: Vigna (Skill 2)
-1 Fast Redeploy: Projekt Red (Skill 1)
-3 Single-Target Snipers: Kroos, Adnachiel, and Meteor (Meteor should be replaceable with a lower-rarity Sniper, I just don't have anyone like that levelled)
-2 [Single-Target?] Medics: Ansel and Hibiscus
-> I didn't use an AOE one here because their tile spacing is weird for this level specifically, idk if you feel the same way
-2 Defenders: Cuora (Skill 2, but Skill 1 should also work?) and Bassline (Skill 2)
-1 Guard: Astesia (she's my lowest rarity levelled guard lol. Shouldn't matter that much tho)

I tried using lower rarity people overall, but I tend to level higher-rarity ones as I get them so I don't have to transition in between. From what I can tell, the ones in this roster should be replaceable, save for Projekt Red, who is absolutely crucial for thinning out the slug armies for me. The reason is that I personally found the terrain hard to work with when it comes to the conventional "snipe them before they come" strategy for both the Casters, Sarkaz Crossbowmen, and slugs, because it felt like my damage dealers weren't dealing damage fast enough for that, so I used a fast redeploy to bridge the gaps. 

I'll run over my strategy (which you don't have to replicate) and pick out key points I saw along the way of my many hecking attempts.

1. Place down the vanguard as soon as possible. I'm pretty sure this is standard behaviour xD
Key point: Vanguard choice (I suck at this one), because they're often crucial for generating DP sufficiently and thinning the crowd sufficiently. This level in particular has a good number of enemies rush at you from the get go. I chose Fang for auto DP generation and Vigna for her damage. 
Key point 2: Vanguard placement. I tried putting Fang up in the top row first, but she kinda just got run over due to not dealing enough damage. So Vigna is up there due to being a better placement. Second point, my horrible spatial imagination did me in a few times 'cause I put the vanguard too close the exploding slugs, and when my single-target Sniper got the ones in the middle left (2nd column, from left to right), I exploded my own vanguard. Not proud of that.
Key point 3: Skill timing. I have an issue where I tend to use skills too late due to forever saving them. In this case, Vigna can only block 1 enemy, so when I saw 2 enemies rushing at her, I needed to activate her skill just before they got within range so one would die quickly and the other one would get blocked.

This level felt like it really hammered in the importance of having a good start

2. Single-target Sniper deployed ASAP to get as many hits on the slugs as possible before the Reunion soldiers come running in


3. Defender (Bassline) deployed in front of Fang to give her some slack on approaching enemies. I don't undeploy Fang yet so she can keep generating DP. Btw the placement of the Defender in front is to try to form a bit of a wall between the explody slugs if they start advancing and the backline, but I didn't have the best grasp of this so lol. I don't think this is a crucial step, but I did it for my own peace of mind. 
4. Deployed Projekt Red in the in-between time to get some of the slugs on the right. In prior improvised strategies, I used a Single-Target Sniper over there, but this is probably the more efficient way. I dunno if you have someone like Red but it's gonna be super helpful later

5. The slugs start moving. Undeployed Vigna, and in front of her I deployed my second Defender (Cuora). This is crucial 'cause if you don't get a Defender there and let Vigna deal with it, she will explode, which is kinda gruesome. 
6. Single-Target Sniper (Adnachiel) facing right to get rid of the approaching drones, and a Medic (Ansel) facing everyone else to cover them. You do need the Medic btw, because the slugs will explode and injure Adnachiel pretty severely. Btw, I struggled a lot with figuring out whether to use an AOE or Single-Target Sniper, and I cannot tell you how many runs I nearly botched by just making the Sniper face the wrong direction lol. Silly 
Key concept: Deployment timing for a lot of this which I suck at when not improvising lol

Key point 4: If you deploy these two too fast the explody slugs will get them. So deployment timing is a thing (I am guilty of deploying Medics too fast out of anxiety, but sometimes they're just not needed yet, and in this level in particular putting them down too fast is instead the worse choice)
 
7. Second Medic heals the first Single-Target Sniper (Kroos). 'Cause the approaching Casters will try and snipe her and her damage is needed.

8. Projekt Red finishes the remaining slugs on the far right column because the approaching wave of them will be brutal and I don't want extra firepower over there on the enemy side.

9. AOE Sniper (Sesa) deployed
Key point 5: Placement of medic. Idk how many runs I botched by making it so my 2nd Medic (Hibiscus) couldn't cover both Snipers lol. 

10. The slugs will start attacking from behind. Undeploy Fang before the second slug is killed, or even earlier if you would like.
Key point 6: Undeploying the correct units and stalling when you need. I let Fang get a few hits in on a slug to kill it a bit faster (to decrease the amount of work the Defenders need to do with their blunt force weapons lol) but undeployed her as soon as possible, or the Medics wouldn't have time to heal everyone and the explosion would kill most of the melee Operators (and probably the Medics, and Snipers too). Since no enemies are approaching anyways, it's ok to let the Defenders duke it out with the slugs to buy time for the Medics. This was a lesson learnt the hard way lol

Key point 7: Discerning enemy type. Here you can see the threat is mostly slugs and killing the ones close to you too fast will mean death. Unfortunately I hecking suck at this

Btw if you need to use Medics' skills just use them. I personally think the slugs are a bigger threat than even the Casters. So key point 8: Skill timing (watch the situation and adapt)

11. Auto got Cuora off the field/incapacitated, which I think is okay even for auto...?
I blocked the slugs coming from the top with Red. But she finished the job so fast I didn't have time to screenshot
Current lineup looks like this:


12. Activated Sesa's skill

Key point 9: There is probably better timing but idk, I waited for the second group up top to be a bit closer so to not waste the skill effect, and that's the best I can do rn lol.

13. Projekt Red stalling the Caster and killing the slug before they make it closer to the frontline

What matters is what she's doing, not the timing or spatial placement. 
Key point 10: These enemies are slow. I needed to realise that to not panic and put operators outside of the Medics' range. Ikr lol.

14. Deployed a guard (Astesia)

Cue auto panicking lol (it's fine)

15. Deployed last single-target Sniper Meteor to finish off the last wave, but now that I look at it, this is probably not necessary, and you could use her slot to replace Projekt Red's function or whatever else you might be lacking on, like healing or a melee Guard. Again, most of my Guards are higher-rarity, but I can see a Lord Guard being helpful to make sure the Drones don't get through in addition to standing behind the Defenders and stuff


Mission accomplished!
Sorry if this is absolutely not helpful at all lol, but maybe seeing someone else's strategy can be interesting to you? (it is for me xD hopefully this isn't just the most boring post ever)

A good point I think might be helpful is to look at a mission in phases. Usually you get stuck on one phase rather than just the entire thing. For instance, I usually did ok with everything except for the slugs. Timing when and how to kill them was a big thing, in addition to how to block them efficiently and heal on time. That was probably the hardest thing for me while redoing (again, in my initial attempt I think I just bullcrapped my way through cycling DPS operators or something lol, it was ok but not the greatest tactically speaking)
Don't beat yourself up for the fundamentals. It's normal to be learning mechanics and re-learning them as you progress. I don't think most people know how to use them 100% after the initial stages xD

Also just to make it clear, I feel the same way sometimes. I have retried WB-9 so many times but can't get past it. I'm still progressing more than I did in previous events, though, so I count it as a win anyways. Sometimes we need to count some "maybe" wins as just wins to keep improving xD

-Galaxian-