Is this a trap?

Sorry to spam the forum with questions, but I just found a large chest on GC1 that contained:
An Arcanite Helmet
2(!) Amulets of Life saving
A Mithril two handed sword
Vermis
A Magic Whistle
A Whip of thievery

is this a trick? It was a regular wooden chest with a triangular lock, so I don think it would have come from a hidden room.

Probably mirrored items, I believe there's a specific entry for chests containing huge mirrored loot.
That is to say, they'll disappear but you can make use of them while you can. Maybe some of the items aren't actually mirrored and others are? Only time will tell.

Can I Sell mirrored items? would be a good test.

all gone. I knew it was too good to be true.

Pity that they all disappeared. I definitely had that trick played on me before, though it was just 1 item (flaming valpurium sword)

P.S. Never apologize for posting IVAN-related threads

Yep.

If a chest full of unbelievably awesome loot appears, it's a trap.

If you find a valpurium flaming sword, it's a trap.

If you find a large room full of loot, it's a trap.

The game is full of traps.

Unfortunately anything that doesn't seem like a trap can also be a trap, meaning that pretty much the safest way to proceed is to treat the entire world like a trap.
At the very least you can count yourself lucky IVAN doesn't have things like, say, pre-determined ambushes full of hideous creatures which trigger upon entering a certain tile or taking a certain item, or things like DoomRL's lever which turns the entire floor into lava.

Well unless we wanted it to, now that we kinda have dev up.

Levers of Lava Revealing, hells yes.

Though that'd make belts of levitation horribly overpowered.

"Bonanza!!!.....oh wait, what does the sign on the other side of the room say? Let me walk over there and check"

Kaboom.