This is not a walkthrough. This is a checklist of things that can be missed in each area. Although nothing in the game is permanently missable (with the one exception of ending Y), the chapter select for replaying any part of the game unlocks only after you fully complete the main story. This checklist is for getting as much as possible done during the main story.
Directions. This checklist uses two kinds of directions — absolute (north, south, east, west, etc.) and relative (left, right, up, down). Follow absolute directions using the minimap with rotation switched off; the relative ones are for areas with fixed side-scrolling or top-down camera.
Routes: When you play the game for the first time, that's route A. After you finish the game, you can continue from the same file and start again, this time with a different character — that's route B. Continuing after route B will bring you to route C, the third and last part of the main game.
Persistence: All fully completed side-quests and open chests remain so permanently; the only exception to this is Abandoned Factory, where the chests reset when you start route B. You also retain all your items, chips, weapons, pods, levels etc. Things related to main story quests, as well as any shortcuts you've opened, get reset between routes A and B.
Route-common: The vast majority of quests and items are "shared" (can be done by during either) between route A and route B, but not route C. These have no special labels in this checklist.
Route-specific: Items that are specific to a route are labeled
route-c. These are things that can only be completed in that route. There are two quests in the game that can be done in either of all three routes, these will have all three labels.
Character-specific: A few quests in route C are available exclusively to 9S or A2. These are labeled
Endings: There are 5 "main" endings (A through E), which incrementally tell you the game's story and which you get by playing the game. Getting ending C or D depends on who you choose for the final battle on your third run of the game; however, after the ending you unlock the ability to replay any previously completed chapter so you can go back and see the other ending whenever you want. Once you have seen both C and D endings, you will be given a chance to play a minigame during end credits that, when won, will unlock ending E.
The other endings (F through Z) are "joke" endings that you can get by failing or performing specific actions in the game. All of them do end the game, so make sure you do them as close to saving as possible so as to not lose as little as progress as possible.
Getting around: You can speed up your travel by riding animals, by using Animal Bait or having Choice Sachet in your inventory. As you progress through the main story, fast travel will also unlock between access points. Most side quests become available not long before that, so it's efficient to postpone doing them until then.
Shops: Check shops in all new areas you discover. Different areas have different items for sale, and new items are sometimes added after major story events.
Evade distance: You can hold down the
evade button to glide further than just by tapping it. This can be further extended with Evade Distance Up chips.
Long jumps: You can massively extend your jump distance by combining all the aerial moves in the game. You can double jump, have your pod throw you (
jump buttons) and evade while in the air, and light attacks also keep you in the air and move you forward for a bit. Finally there's the glide (hold
jump button while in the air) for landing slowly while still moving slightly in a chosen direction.
Hacking: Lock-on works in hacking, even though there is no visual indicator.
Counter: You need to equp a Counter chip to be able to counter enemy attacks (different from evasion counters, the method is in the chip's description). Nearly every melee attack in the game can be countered, and with higher chip versions the move returns damage back to the attacker. At +8 the damage returned is 250% the damage you would have received, so it's a move worth learning, especially if you're playing on harder difficulties.
Chip capacity: It's worth upgrading you plug-in chip capacity as early & quickly as possible, especially if you're planning on doubling your drop rate and/or learning the counter move early in the game. More efficient chips (with lower space requirements) can only be found randomly in loot drops, the ones from shops always take up maximum space for that chip level.
Chip efficiency: While for most chips +8 is the only way to get the maximum out of it, there are a few exceptions where combining multiple low level chips can get the same effect easier and/or using less space. See reference for specifics.
Double drop rate: Equipping Drop Rate Up +3 and Drop Rate Up +4 plug-in chips together is the most efficient way to nearly double (+90%, the maximum possible) the amount of items the enemies drop when killed. The earliest opportunity to get it is by buying 24 Drop Rate Up chips from the shop in the village, and then fusing them into +3 and +4 versions at the resistance. The total cost for buying and fusing all 24 is $49000 and they will require 30 slots of space to equip.
Critical attacks: A critical attack deals 500% damage, so a weapon with "Critical +" effect can be a good source of overall damage, even if the listed damage numbers are mediocre. Equipping Critical Up chips improve this further: a Critical Up +8 chip gives you +30% critical chance, which means you get 500% damage every three hits on average — the equivalent of having +60% damage overall. See reference for the weapon list.
Fish for $: If you need money, especially early in the game, do some fishing and sell what you catch. Most fish can be sold for couple thousand $ each.
What to sell: You can safely sell any item whos description says "can be exchanged for money".
How: You can fish at nearly any body of water, either standing in it or next to it, on a bridge, etc. Hold down the
action button to start, and then use the
jump button to throw your pod into the water. Whenever it goes fully under the water, or if it starts moving against the current (if there is a current), press the
jump button again to reel it in. In some spots there is no current, in which case you just have to reel the pod in if it hasn't dipped in a while and hope it has caught something.
Rarity: Rare and very rare fish can be ridiculously hard to get. Catching a very rare fish can literally take hours and there is no way to increase the odds of getting any one specific fish.
What to catch: This guide doesn't contain every fish in the game, instead, fishing checklist groups less common fish by areas where they are more likely to be caught than in others. By the time you catch each of these fish in the areas indicated, it's virtually guaranteed that you will also have caught every other (more common) fish in the game. The information on fishing is based entirely on the fishing section of PuppyLand's Nier: Automata guide at GameFAQs.