Eva is one of Hollow Knight: Silksong’s most consequential NPCs. Hidden away in Weavenest Atla, she upgrades Hornet’s combat kit and, later, can be “bound” for a persistent quality-of-life perk. If you’re hunting for that late-game prompt and the related achievement, here’s what actually moves the needle — with enough detail to get you there without detours.

How to reach Weavenest Atla and meet Eva

Weavenest Atla sits behind the spider-marked gate you likely noticed in Moss Grotto early on. You can’t open it until you’ve acquired Needolin, an Ancestral Art rewarded after defeating Widow in Bellhart. With Needolin in hand:

  • Return to Moss Grotto and play Needolin at the spider gate to unseal it.
  • Inside Weavenest Atla, head right past the first chamber. In a side room, strike the two ceiling triggers to light the area and reveal the local map.
  • Step onto the central device back in the main chamber to beam down. From here, go right and break several walls to reach Eva’s chamber.

Eva will initiate a conversation on first contact and immediately offer upgrades tied to Hornet’s Crest system.

What Eva changes on first visit

On the initial meeting, Eva applies a direct upgrade to the Hunter Crest and unlocks an additional Tool capacity tied to the “yellow” slot group, expanding your build options. The net effect is a stronger baseline Crest and room for one more utility Tool in core combat routes. You can revisit Eva after certain progression milestones to receive further upgrades.

Useful stops inside Weavenest Atla (optional but worthwhile)

While you’re here, there are several quick grabs that meaningfully smooth midgame and beyond:

  • Bench and hidden passage: From the beam platform, go left to a bench. Drop into the water beside it and swim left through a hidden path that reconnects into Moss Grotto-style caves.
  • Moss Mother rematch: Continue left to a familiar arena where you’ll face two Moss Mothers at once. The reward is the Weavelight Tool, which accelerates silk regeneration.
  • Spool Fragment: In a room above/right of the main chamber, take out two Marrowmaws and snag the fragment floating in the adjacent shaft to expand silk capacity.
  • Rune Harp: Climb the main vertical shaft toward the top and branch right to find a Rune Harp collectible.
  • Mask Fragment: From the bottom of that shaft, break the right wall and navigate a brief lava platforming section to claim a Mask Fragment.

Binding Eva: what it does

Binding Eva is a late-game interaction that permanently enables silk restoration at benches and triggers an associated in-game achievement. The feature functions like a passive blessing: rest to refill silk in addition to your masks, removing a common resource tax between attempts or long routes.

The checklist that reliably triggers the Bind prompt

There’s no explicit quest log for Eva, and the trigger is easy to miss if you’ve split your upgrades across multiple Crests. Players who’ve successfully bound Eva tend to have the following in place:

  • Collect a broad set of Crests. The prompt appears after substantial Crest progression — not just the starter set. Early Crests include Hunter, Reaper, Wanderer, and Beast; additional Crests surface across Acts 2–3. You do not necessarily need every single Crest, but having “most” dramatically improves your odds.
  • Spend Memory Lockets on Crest slots, prioritizing Hunter. Memory Lockets unlock extra Tool slots on a Crest by color (yellow, red, blue). Use enough Lockets to expand the majority of your owned Crests. A common pitfall: never investing a Locket into the Hunter Crest. Fully expanding Hunter first has consistently coincided with unlocking Eva’s Bind option.
  • Revisit Eva after upgrades. The Bind prompt won’t appear mid-run. After slotting Lockets and picking up any new Crests, return to Weavenest Atla and talk to Eva again.

Tip: Memory Lockets are rare. If you’re short, funnel them into Hunter, then your most-used Crest. You can circle back to round out the rest later.

Help: no Bind prompt yet?

  • Double-check Hunter Crest expansion. If Hunter is the only Crest without an invested Memory Locket, fix that first and revisit Eva.
  • Add one more Crest or slot. If you’re late-game but still stuck, pick up an additional Crest you skipped or open another slot on a different Crest, then return.
  • Advance a bit further. Some players only saw the prompt after later Act abilities, even with the above. If nothing fires, progress the main path and try again.

What Binding doesn’t do

Binding Eva doesn’t alter your Crest loadout, consume additional items, or remove any abilities. It’s a global convenience that activates at benches and stays on.

Eva, Crests, and Memory Lockets — quick background

Eva frames Crests as a condensed expression of a being’s soul, with each Crest reshaping Hornet’s attacks, healing, and Tool slots. Memory Lockets are the lever you use to open additional Tool capacity on a given Crest, and their slots are color-coded by Tool type. Because Eva’s Bind appears to key off your overall Crest and slot progression, Lockets effectively serve as your gate here too. If you’re chasing the achievement, don’t hoard them.

Leaving and re-entering Weavenest Atla

The Moss Grotto door seals itself between visits. You’ll need to play Needolin each time you pass through to reach Eva again. Inside, the beam elevator remains usable once you’ve lit the triggers up top.

Why it matters

Silk is Silksong’s tempo — it powers movement, offense, and recovery. Turning benches into silk refills reduces friction everywhere, from repeated boss attempts to extended exploration runs. If you missed the Bind because you spread Lockets thinly across Crests, a single Locket on the Hunter Crest is often the nudge that unlocks the option. When it appears, take it; it’s one of the few late-game upgrades that quietly transforms the day-to-day feel of Pharloom.

If you’re still not seeing the prompt after meeting the checklist, keep expanding your Crest roster and slots as you push through the later acts, then make another trip back to Eva. The payoff is worth the detour.