Ecco The Dolphin Wiki

The "Death Replicator" is a given name to the cyborg enemy found within Level H of Ecco 2 Alpha. It is a creature exclusive to E2A, as it was cut from the final release of Ecco: The Tides of Time.

Having the appearance of a robotic cetacean, it is assumed it was created by the Vortex specifically as a weapon to fight Ecco, suggested by its shape and method of movement. It can charge at Ecco at high speed due to a propulsion engine at its rear. A thick drill is also installed within its chest, and can protrude at will to stab Ecco. Although it cannot harm Ecco (technically) due to the E2A build, it should be considered a dangerous and capable enemy. The cyborg would have served as a boss had it made it into the final release.

While in combat with the Replicator, a crab can be seen scrolling across the top of the screen dropping exploding canisters of some toxic liquid. The crabs purpose seems to mirror the Replicator, as it acts in tandem with the enemy. It cannot be killed but disappears upon the cyborg's destruction.