Crono inspects a mysterious sealed chest in Chrono Trigger. This one is located in Truce, Crono's home town.

Main Walkthrough

Early on in Chrono Trigger - more or less immediately after you start the game, in fact - you'll start running into sealed, black boxes. Usually (but not always) located in populated locations, and occasionally appearing in multiple time periods, these chests will not open when you first find them, and are described as being sealed by a mysterious force. You won't be able to open them until you power up Marle's Pendant via the Mammon Machine, during your first visit to Zeal Palace in 12,000 BC.

This guide will lead you to all of the sealed boxes in Chrono Trigger. They all contain powerful items that will prove handy over the course of your playthrough. This guide will also cover the sealed doors that appear in 2300 AD, which similarly contain useful items, and also require Marle's Pendant to open.

Crono decides not to open a sealed chest in 600 AD, an era in Chrono Trigger. Inspecting sealed chests but not opening them right away can lead to item upgrades in later eras.

Powering Up

As mentioned above, it's sometimes possible to find a sealed chest that appears in multiple time periods. These chests are always found in 600 AD and 1000 AD, since both eras share similar maps. There are two obvious ways to approach these sealed chests:
  • You can open the chest in 600 AD. If you do this the chest will disappear from 1000 AD.
  • You can open the chest in 1000 AD. If you do this the chest will still be in 600 AD, and you can go back and collect the item again.
In this scenario it is smarter to open the chest in 1000 AD, then hop back in time and open the same chest in 600 AD. That said, there's an even smarter approach to this process, and that's to check the chests in 600 AD but do not open them. When inspecting a sealed chest in 600 AD you'll have the option to leave the contents alone, and if you do this Marle's Pendant will imbue whatever's inside with extra power. Travel to 1000 AD and the item will receive a power-up, becoming a superior version of itself. You can then skip back to 600 AD and get the original item.

It's important to note that you won't find extra copies of all of the sealed chests in 600 AD and 1000 AD. The chests don't move too far from their original spots, so if you didn't see a chest in the same spot in the second era it probably only exists in the first.

A sealed chest inside the Magic Cave, an extremely short dungeon in Chrono Trigger.

Sealed Chests - 600 AD
  • Truce - Inside the Inn, by the beds - Contains a Blue Vest (upgrade available)
  • Guardia Forest - Northern path, east of the exit to Guardia Castle - Contains a Speed Capsule (no upgrade)
  • Porre (2 boxes) - In the Mayor's Manor - Contain a White Vest and a Black Vest (upgrades available)
  • Guardia Castle - On one of the floors up the western tower - Contains a Red Vest (upgrade available)
  • Magic Cave - Along the short path through the cave - Contains a Magic Ring (no upgrade)
  • Northern Ruins - In the room on the right as you're heading north through the second level - Contains Nova Armor (upgrade available)
  • Northern Ruins (2 boxes) - At the end of the northern path on the second level - Contain an Onimaru and a Siren's Kiss (upgrades available)
The team opens a sealed chest and acquires White Plate, a useful piece of armor in Chrono Trigger.

Sealed Chests - 1000 AD
  • Truce - Inside the Inn, by the beds - Contains a Blue Vest / Blue Plate
  • Guardia Forest - At the dead end with the Gate; only accessible by traveling back through 2300 AD to Bangor Dome - Contains a Power Ring
  • Porre (2 boxes) - In the Mayor's Manor, second floor - Contains a White Vest / White Plate and a Black Vest / Black Plate
  • Guardia Castle - On one of the floors up the western tower - Contains a Red Vest / Red Plate
  • Heckran Cave - In the western-most room, just before entering the water to travel to Heckran's lair - Contains a Barrier Ring and a Speed Ring
  • Northern Ruins - In the room on the right as you're heading north through the second level - Contains Nova Armor / Moonbeam Armor
  • Northern Ruins (2 boxes) - At the end of the northern path on the second level - Contain an Onimaru / Suzaku and a Siren's Kiss / Valkyrie Bow
A sealed door beneath Arris Dome, one of the locations in Chrono Trigger.

Sealed Doors - 2300 AD
  • Bangor Dome - Behind the Gate - Contains a Full Ether, an Alluring Top, and a Workman's Wallet
  • Trann Dome - On the west side of the dome - Contains a Magic Capsule, a Golden Stud, and a Hi-Ether
  • Arris Dome - In the basement, a little ways east of the room with the computer that introduced Lavos - Contains a Strength Capsule, a Luminous Robe, an Elixir, an Acuity Ring, and a Golden Earring
The sealed pyramid, a mysterious location in Chrono Trigger that can only be opened when you've reactivated the powers of Marle's Pendant.

Sealed Pyramid

In addition to the chests and the doors there's another little treasure trove that you can open with Marle's Pendant. Travel to Medina Village in 1000 AD and check out the blue pyramid to the north. The pendant will dispel the pyramid, revealing a Nu and two sealed chests. You can choose one of the two chests:
  • The right chest contains the Swallow, a weapon for Crono
  • The left chest contains a Guardian Helm, a piece of equipment
Both items are useful, but the Guardian Helm has greater staying power since it grants a permanent Protect status to its bearer. Still, the choice is yours.