Internal organelle requiring 30 seconds of overcharge time to activate with 1 charge.
When activated, the ribosome would generate several (4?) irregularly-shaped shield-like protein structures around the pathogen to act as barriers. Each structure would have 3 hp and could fully block both projectile and melee attacks, though when hit each structure would be knocked back slightly. Your pathogen's projectiles would also be blocked by the structures, though your melee attacks would not.
Each upgrade tier would decrease overcharge time by 3 seconds and rare and legendary upgrades would increase protein structure hp by 1.
If activated when overcharged, structures would be 15% larger.