It is a giant Big Core MK I that appears in Otomedius Excellent. It's unknown if it has a pilot.
One of its laser cannons on the front shoots down Meta Lium's Big Core DX before the player makes their approach. When the player reaches the laser cannon, it fires off to the side before Old Big Core moves and floats most of the way out of the water.
To fight Old Big Core, the player heads inside the path left open, as there are no solid barriers impeding forward progress. As it turns out, the inside of Old Big Core is a Gunwall situated in front of the actual full-size core to the ship. There are two smaller mini-cores, one on either side of the central core, which is about as big as the player (if not a little bigger). The top and bottom edges of the three leftmost barrier sections have turrets, and together will fire a concussive laser to restrict movement; then each will fire a normal shot at the player. To prevent the concussive laser attack, take out either side of each pair.
The main threat, however, is the moving turret on the final barrier section's rail that moves up and down with the player and fires two rows of normal shots. Sacrificing a hit on the force field to move past and get behind this moving turret gun is the best option for destroying the gunwall's three cores. Destroying the weapon is not advised unless the player needs to do so in order to obtain a weapon card in a certain loop and difficulty.
|Big Cores||Big Core MK I • Big Core MK-I Rev.2 • Big Core MK II • Big Core MK II Kai • Big Core MK III • Big Core MK IV|
|Big Core variants||Beacon • Blaster Cannon Core • Bubble Core • Circle Core • Coreship • Crater Core • Crystal Core • Dellinger Core • Desert Core • Heaven's Gate • Juggler Core • Laser Core • Lizard Core • Neo Big Core • Perla Meralda • Rexion Core • Rolling Core • Shining Core • Super Big Core • Terra Core • Vanishing Core • Genocide Core • Odin Core|
|Core-style bosses||Abaddon Warship • Covered Core • Covered Core MK II • Dead End • Kraken • Mayhem Warship • Metal Slave • Misfit Warship • Queensrÿche • Riot Warship • Plate Core|
|Pseudo-Cores||Death • Death MK II (DeathDouble) • Death MK III • Beta Core • Nobil • Triple Core • Crash Bam|
|Tetran variants||Tetran (Zylom) • Covered Tetran • Crystal Core D-X02 • Laser Tetran • Tenny Rop|
|Parody Cores||Candy Core • Decoration Core • Decoration Core MK II • Viva Core|