Deadlock Tunnels Guide: Who Fits, How to Enter and When to Use Them

Rat King disappears into a tiny passage. You follow, hit the wall and lose several seconds while he gets on with his game. Character size explains surprisingly little: a large hero can have a special entry action while a seemingly suitable hero has no access at all.

This guide covers the small tunnel passages, not every staircase or road below street level. Their entrances have hero restrictions. Check access first, then your approach, before deciding a particular entrance is broken.

The information below reflects the game as checked on October 13, 2026, after Rat King’s release. You do not need to memorize the entire tunnel network to start making useful decisions.

In a standard match, Calico, Rem, Mo & Krill and Rat King can use these small passages, but their entry requirements differ:

Simply crouching on another hero is not enough. Looking small enough does not replace an entry requirement either. On Calico, watch Ava’s remaining duration: complete your route while the required form is active.

The practical consequence matters more than the list: your teammate may be unable to follow. When escaping together, taking a tunnel can split you up precisely when you need each other’s help.

Check your hero’s form and the situation first. Recent damage can temporarily block entry, so do not expect to dive into an opening while taking uninterrupted fire. Break contact before trying the passage.

For Rem and Mo & Krill/Rat King’s special entry, try this sequence; on Calico, activate Ava first:

Do not treat a dash or full-speed slide into the opening as a universal entry command. A controlled crouched approach is easier to troubleshoot because fewer inputs overlap and you can see whether the entry animation begins.

This is an entry check, not a guaranteed fix for every bug. If it fails, avoid spending the entire useful moment of a match repeating the same movement.

A failed attempt does not prove that the hero lost tunnel access. But insisting that it should work while enemies shoot at you is not helpful either. Choosing a different route in time matters more to the current fight.

Do not plan around the entrance as an instant invulnerability button. Alongside the restriction after damage, Mo & Krill and Rat King have a distinct animated entry action. Plan the route early and keep an ordinary escape route available in case entry is currently blocked.

A useful tunnel is one where you know at least two things: where it leads and what you will do immediately afterward. Leaving an enemy’s view achieves little if you emerge exposed next to someone else.

In Explore NYC, choose one passage and travel through it in both directions. Note a landmark at each end and the nearest ordinary route connecting those areas. Then approach from the direction you commonly arrive during a match.

You do not need a complete map to begin. One route you recognize while moving is more useful than five entrances whose exits you cannot remember. Once that route feels familiar, add another near a part of the map you regularly use.

A passage is useful when it serves a specific purpose: creating another angle, losing a pursuer after breaking contact or fitting naturally into your movement between tasks.

Check where enemies are, where teammates are and where you need to go after the exit. If your team is already engaging, entering just because there might be something to collect can become an expensive delay.

Tunnels are not guaranteed safe rooms. An enemy with access can take the same passage. Rat King’s arrival makes that especially relevant: a route that blocks one pursuer does not have to stop another.

The September 16 patch changed breakables in underground tunnels: their initial spawn moved from 3 to 5 minutes, and their respawn interval also moved from 3 to 5 minutes.

That rule concerns breakable objects. It does not promise that every passage always contains something to collect. Another player may already have cleared it, and checking does not always justify the time spent.

A good habit is to include a tunnel when the route itself is useful. If a speculative detour means missing an available wave or arriving late to your team, compare those concrete losses with the purpose of the trip.

For using these passages on the new hero, see the Rat King guide. If you are chasing him or trying to survive his approach, read how to counter Rat King.