To open the secret tomb and unearth the dead, first of all, you will have to keep in mind that the mechanics, the coffin's location, and what we find there have changed regarding the alpha and beta versions of the game, that involved unearthing a teacher's mannequin. Now, the story is quite different. For starters, the coffin is now unearthed in Act 2.

First, in the raft room that we emptied to "kill" the shark, there should be a shovel on a carpet near the door at the back:

Shovel in the shark roomShovel in the shark room

We pick it up and walk through the door, now located behind us. In the room where we will arrive, we will see that there is a hole in the floor. We will go there to take a shortcut:

Shortcut through the hole in the floorShortcut through the hole in the floor

Upon landing, we will find ourselves looking into a window. To the right, we have a doll's house, and to the back, a door. We have to go through that door:

Door to enter the loftDoor to enter the loft

We will get to some kind of attic. We will have to go straight ahead to reach the stairs that go down. To the left is a door, next to it, hangs a key. This key opens the lock on the door. We take it and open it:

Door to get out into the house’s hallwayDoor to get out into the house’s hallway

If we cross through this door, we will arrive at the house entrance. If we go out through the door that is right in front of us, we will arrive at the garden. Now, we can go and unearth the coffin, located at the back of the building and aligned with the entrance to the basement, from where you begin the second act (which is a nightmare of the protagonist). When you get to the back of the house to unearth the coffin, you should be in exactly this position to do so:

Exact location of the coffinExact location of the coffin

Now, you can start digging in the disturbed earth that you will see at your feet. You will reach the coffin, and when you open it, you will see that it contains a key. Nothing is really dead:

Unburied coffin and keyUnburied coffin and key

Hello Neighbor has artificial intelligence that learns from the decisions made by the player, complicating the game while learning the player's escape and movement patterns.