Dungeons and Dragons 5th ed magic item "Seraph’s Boxes of Mysteries"

Seraph’s Boxes of Mysteries.

The good wizard Seraph wanted to create a box. A box containing a perfectly warm, safe place for his pets to travel with him when he was on the road. He tried many times, but each time another failure. These items represent his best attempts. Four identical boxes one he kept, and one gifted to his son in law as part of the dowry, and two gifted to local lords / patrons as thanks for their tireless support.

Physical Description:

Each box is exactly two cubic feet, made of a fine hardwood stained deepest black. All of the panels edges are reinforced with thin strips of iron.Each box has a well crafted lock (DC 20 to pick) and latch on it’s lid. This latch allows the whole top panel to be removed. The interior of the box is lined with purple velvet, the interior surface opposite the lid is a endlessly ebbing and flowing pool of darkness.

In play:

• Any item that can fit into the boxes opening can be placed in the box.
• The box can hold up to 20 items. There are no size limits except the following
• Small items weighing less than 2 pounds must be put into a bag or other container in such volume that they weigh 2 a total pounds or more. 
• Small single items or loose liquids (Liquids less than 2 cubic feet in volume) that are tossed in the box regardless of their numbers, are simply swallowed and are lost.

• The player should keep a list from 1 to 20 of the items placed in the box.
• Fill the list in starting at 20 and working back to 1.
• Only the four most recent items placed into the box (top of the list) are visible bobbing around in the darkness when the box is opened.
• These items may be removed form the box (1 action)

• If the player wants a different time them must shove one visible item into the dark (1 action) and it will trade places lower down on the list with another item which had been placed int the box. (roll 1d20 to determine what slot on the list the item swaps with) If an empty space is rolled nothing rises back to the surface.

• Theoretically if there weren’t many items in the box a player could push everything into the darkness and have nothing visible at the surface and this situation would persist until more items were placed in the box and used to bump the old items back into reach.

• Living creatures placed in the box will survive but will not have anything to eat unless they have it on their person.
•  Creatures can not get them selves out of the box, unless it is functioning strangely (see below) 
• Only small creatures can have any chance of getting in the box, most humanoids shoulders are just too broad.
• Placing a portable hole or other dimensional object in to the box has no adverse effect on either item.

• The box can not be tipped out or spilled.

• The box is magical and can not be destroyed by any normal means except fire. 
•  The box saves at +10 vs normal or magical fire.
•  After 20 points of fire damage it burns up, randomly scattering any items placed in the box crossed a 100 mile radius.

The box is not 100% predictable.

Whenever the box is opened roll 1d12

1. The box looks empty! Give it a good shake (1 action) and 4 random items stored within the box will bubble up to the surface.
2. A cat jumps out, its friendly and loving, roll 1d6 1-3 it’s a calico 4-6 it’s a tuxedo.
3. 1d12 toads issue forth.
4. Nothing happens normal operation.
5. It makes the resonant sound of a large church bell ringing, just once. Each creature in a 10-foot cube originating from the box must make a Constitution saving throw Vs DC 12. On a failed save, a creature takes 1d8 thunder damage.
6. Smoke billows out of the box granting anything in the smoke half cover.
7. Every item in the box is visible and available!
8. Nothing happens normal operation.
9. The box shines lights as per the evocation cantrip “Light” for the whole time it’s lid is removed.
10. A great cloud of butterflies issues forth.
11. A random item you never put in the box floats to the surface. This item is from one of the other three boxes. (DM Decides the item)
12. It disgorges any items stored within all at once.