Major Items of Progression

Major Progression Items
Mothwing Cloak / Shade Cloak - Allows you to dash horizontally on the ground or in the air, while Shade Cloak adds the ability to dash through enemies and shade barriers. Finding this item early opens up some locations such as Salubra’s Shop and Fungal Wastes, which can lead to other map locations.

Mantis Claw - Gives the player the ability to cling to walls and wall jump. Finding this item opens up the entire game, almost. Early on you can skip the Baldur fight in Ancestral Mound for an item check, go to Salubra’s Shop, or head back up the Dirtmouth entrance to King’s Pass leading to other map locations.

Monarch Wings - Allows you to double jump in the air. Doing a pogo off an enemy or background object allows you to do another wings jump after each pogo. Finding this item early opens up some locations such as Salubra’s Shop and Fungal Wastes, along with some early item locations that require Wings, such as the Goam Room Mask Shard in Forgotten Crossroads.

Crystal Heart - Once charged up and released, this allows you to super dash horizontally across large gaps and distances, until the dash is manually canceled or you crash into an object (wall/enemy). Finding this item early gives you access to Salubra’s Shop, by crystal dashing from Gruz Mother’s arena.

Isma’s Tear - Allows you to safely swim through acid. Finding this item early in the game will give access to Fog Canyon through the southwest exit of Forgotten Crossroads, through the acid pool. Isma’s Tear is mostly beneficial in locations with several acid hazard spots, such as Queen’s Garden and Isma’s Grove.

Spells
Boss logic depends only on spells. For example, on easy logic, "Aerial Minibosses" (dream warriors and Uumuu) require either VS or Wraiths, "Minibosses" (like Brooding Mawlek) require any one spell level, "Bosses" (like Troupe Master Grimm) require any two spell levels, and Flukemarm requires either Shade Soul or Abyss Shriek.

Vengeful Spirit / Shade Soul - Shoots a damaging projectile while you have soul stored. Minor progression item In Easy Logic, which is mostly used for combat progression; such as fighting Baldurs in Ancestral Mound and the Baldur blocking access to Greenpath. In Hard Logic, these are used for many sequence breaks using Fireball Skips. When using VS/SS, use the ‘Quick Cast’ button for faster spells instead of the ‘Focus’ button.

Desolate Dive / Descending Dark - Allows you to slam into the ground while dealing damage to enemies and breaking through floor barriers. DD early on can be used to kill early Baldur enemies, and also gives access to Crystal Peak by diving through the floor barrier past the northeast Forgotten Crossroads exit. When using DD, use the ‘Quick Cast’ button for faster spells.

Howling Wraiths / Abyss Shriek - The greatest spell in the game, no, the greatest item in the game. Hollow Knight and Radiance will quit the game and file unemployment once you obtain this spell. Howling Wraiths does not provide any progression in Easy Logic other than for bosses, but in Hard Logic it shares most of the same setups as Fireball Skips. When using HW/AS, use the ‘Quick Cast’ button for faster spells.

Nail Arts
There are a total of 3 Nail Arts: Great Slash, Dash Slash, and Cyclone Slash. Obtaining all 3 unlocks the Nailmaster's Glory check inside Sly's Shop in Dirtmouth. In addition, Dash Slash and Cyclone Slash are Baldur-killers in Easy and Hard logic, respectively.

All nail arts also have uses in performing lever skips, and can also be used as airstalls.

Keys
Simple Key - A total of 4 Simple Keys can be found in the game. Your first found Simple Key must always be used on the Royal Waterways entrance below Lemm’s Shop in the City of Tears; the game won’t allow you to use your first simple key on anything else. In addition, all other simple key uses are only in logic once you have all 4 simple keys.

Elegant Key - Unlocks the door to access the Shade Soul chamber, near the Toll Bench and Cornifer location in Soul Sanctum.

Shopkeeper’s Key - Take this key to Sly’s Shop in Dirtmouth, after he has been rescued from Forgotten Crossroads. Will unlock more items for purchase.

Love Key - Unlocks the Collector’s Lair with 4 checks inside, depending on randomization options. Mantis Claw or Monarch Wings will be required to navigate this area.

City Crest - Gives access to the left side of City of Tears. Is sometimes a progression item, especially if an early Crystal Heart is acquired or if Shade Skips are disabled in the difficulty settings.

Dream Nails and Essence
Dream Nail - The first Dream Nail you pick up gives you Dream Nail. This allows you to fight Dream Warriors and Dream Bosses, activate Whispering Roots (essence trees), and collect soul from enemies. Certain checks require you to have Dream Nail, such as the 3 Dreamer locations and the Void Heart location in the Birthplace.

Dream Gate - The second Dream Nail you pick up gives you Dream Gate. This allows you to drop a warp point you wish to return to later, costing 1 essence each time you use it to travel. Does not unlock any other item progression locations in the game but can speed a lot of things up. This can also be used creatively for setting up cursed double shadeskips, but this is never in logic.

Awoken Dream Nail - The third Dream Nail you pick up gives you Awoken Dream Nail. This allows you to enter White Palace.

Charms
The useful charms for a randomizer generally fall under one of two categories: Those that aid progression and those that aid combat. While the combat charms aren’t essential they make fights such as the Radiance easier and can speed up general exploration.

Progression:
Void Heart - The first two White Fragments you pick up give you Kingsoul; the third gives you Void Heart. Some randomizer races are played to ‘True Ending’, meaning the player needs Void Heart to kill Radiance finish the race, making this charm essential. In addition, either of Kingsoul or Voidheart is necessary to open the Birthplace in Abyss in order to get the two checks there. And finally, Voidheart pacifiess the void tendrils in Abyss, allowing you to check the Arcane Egg next to Shade Cloak without having Shade Cloak.

Baldur Killers - In addition to Desolate Dive, Vengeful Spirit, and Dash Slash, easy logic also includes Grubberfly's Elegy and Glowing Womb as baldur killers. Mild skips includes Spore Shroom and Weaversong, while spicy skips add Mark of Pride (as well as Cyclone Slash and Mothwing Cloak). Sprintmaster, Longnail, and Dreamshield can also be used to kill baldurs, but those are not in any logic.

Dashmaster - Dashmaster can be used for spike tunnel skips if you don’t have an airstall. Also nice for moving around faster.

Sprintmaster - This charm can be used in conjunction with Dashmaster to navigate the crushers in Crystal Peak without Mothwing Cloak. It is also a baldur killer, but not in logic.

Sharp Shadow - The slight increase in dash length can be used to reach the Shape of Unn location without Isma’s Tear, as well as in sequence breaks for Love Key, the acid skip to Fog Canyon from Forgotten Crossroads, and for reaching the upper grub in Queen's Gardens without Crystal Heart.

Grubberfly’s Elegy - This charm, on top of being a Baldur killer, can also be used in a shadeskip to get the chest in Crystal Peak without Mantis Claw.

Grimmchild - This causes the Grimm Troupe to appear in Dirtmouth, with the quest progressed to the Troupe Master Grimm fight, giving access to the initial Grimmchild check and the TMG Charm Notch check.

Glowing Womb - In addition to being a Baldur killer, this can be used to make some shadeskips possible, such as the one at the end of the room with the toll bench in Ancient Basin to get to the Simple Key and Monarch Wings checks without Crystal Heart. These shadeskips are not in any logic

Combat:
Shaman Stone - Increases spell damage drastically, and is the best charm for spell builds. This plus Abyss Shriek makes Radiance much, much easier. Basically never not worth getting.

Quick Slash - Increases nail attack speed by 50%. Theoretically a 50% nail damage increase, but also makes soul collection faster, buffing spell builds. Also useful for breaking breakable walls faster.

Unbreakable Strength - Randomizers have the fragile charms appear as their unbreakable versions, making this charm amazing. Synergizes exceptionally well with Quick Slash and/or Fury of the Fallen due to multiplicative increases in damage.

Fury of the Fallen - Increases nail damage by 75% when on 1HP. Largely useless on spell builds and risky to use, but if you’re confident in your dodging ability it makes nail builds much better. Stacks multiplicatively with Unbreakable Strength, giving a 162.5% damage increase at 1HP.

Spell Twister - Reduces spell soul consumption, which is a nice dps boost for spell builds. It also makes fireball skips easier, such as the one in Queen’s Station, as you can cast one extra spell to get a slightly longer stall.