The Exterminator Prototype is an item from the Better Dungeons mod with the appearance of an iron ingot, possibly only able to be obtained through creative/cheat mode.

2013-08-08 17.26.27

The Exterminator prototype

However, when right clicked, this item spawns a Wyvern, a strange mob with the appearance of a dragon's head. Once spawned they will fly in strange patterns, they occasionally do 2 damage to other entities (including other wyverns) and players.

The Exterminator Prototype behaves as Spawn Egg, becuase when used in Survival, it will be used up, similar to strange spawn egg in Herobrine mod (does nor appear in Hexxit) (Verification Needed)
2013-08-08 17.27.59

A Wyvern

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