From Sonic Retro
The Large Cannon is an upgrade available to Dr. Eggman in Sonic Adventure 2. It upgrades the Egg Walker's Volkan Cannon, which allows it to break not only wooden crates, but steel crates as well. Black metal crates are still unbreakable, however.
- Purpose: An upgrade to the Volcan Cannon so that it can destroy steel containers.
- Location: Weapons Bed. The path straight ahead will have a stack of steel containers, too high to jump over. Go into the center room in the building to the left. The Large Cannon while be behind the door.
- Requirements: None, except that the Jet Engine is incidentally needed to get to this point in the story (and will be required for the level in any case shortly after this item).
- Required For: Nothing in the story--the stack of metal containers can be circumvented in order to advance past the first carrier, as can all similar roadblocks later on. There's finally a blockade of boxes in Iron Gate's final mission can can't be bypassed over or around, marking the one point where this item is required.
- Equivalent: Tails' Bazooka.