The Biomechanoid boss has two phases: The Mortal Phase and the Shield Phase.

In the Mortal Phase Biomechanoid is able to recieve damage. After a certain period of time, Biomechanoid will switch to the Shield Phase, in which a pink-coloured shield will appear around Biomechanoid and soak up all the damage recieved. In this phase, drones will also appear from the sides of Biomechanoid which fly in a straight line towards the player. The only way to get rid of the shield is to use the hammer attack to deflect them back at Biomechanoid. Once this has been done, Biomechanoid will return to Mortal Phase for some time.

Tips
The key to defeating Biomechanoid is mobility. Stay as much in the middle-center as possible all the time, so weapons have enough range to reach Biomechanoid, and there is enough room to avoid the many projectiles Biomechanoid fires off. The Rocket Powered Boots perk is very much recommended for an extra edge in avoiding them. Keep dishing out as much damage as possible in the Mortal Phase, then when the Shield Phase comes around - don't bother, just focus purely on reflecting the drones Biomechanoid fires off. While it's certainly possible without perks, Super Swinger and Hurricane Heels help immensely in fending the drones off.


Check out our Wiki page on Biomechanoid for more info: http://ihrb.wikia.com/wiki/Biomechanoid_(Boss)