Bat

The Level 1 Normal Bats came from a glitch in the Stockpile Crate. This crate was unusual because it held items from many different community creators. It also let players enter a seed phrase to preview the 4 items that crate could unbox.

Some time after the crate came out, a dispute between one of the creators and Valve led to that creator's items being temporarily removed from the drop table. The items were taken out of the drops but were never properly removed from the seed rerolling mechanic.

Black Rain, who discovered the glitch, started typing random words and phrases as seeds, looking for a null value or other odd behavior. Instead, seeds that landed on the removed creator's items pulled item defindex 0, which is the stock Bat. Stockpile Crates sold for only a few cents at the time, so Black Rain bought and opened a bunch of them. About 25% of those crates unboxed a Normal quality Bat. A friend unboxed a couple as well. Then Black Rain emailed Valve right away so the glitch could be patched. Today the crate no longer drops the Bat, but its preview still shows that it might.

The Level 0 Normal Bats most likely came from a different item server glitch or exploit, based on their seemingly default values:

The defindex is 0. Every TF2 item has a unique index number called the defindex, and for Bats it is 0.

The quality is 0. Every item quality has a numerical ID, and Normal quality is 0.

The level is 0. TF2 items can have a level from 0 to 255, and these Bats are level 0.

The origin is 0. Every TF2 item has a numerical origin ID, and for these Bats it is 0 (Timed Drop).

There are 5 Level 0 and 9 Level 1 Normal Bats in existence.

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