This adjustment abandons the shotgun approach for a different approach as follows:
Buffs:
Damage: +25% (to 3000)
Health: +90 (to 100)
Turn speed: +a lot
Fuel regen: +infinity% (to 3, from 0)
Nerfs:
Tracking: Homing removed (No longer tracks target, tracks target ground instead)
Miniprojecile velocity: All mini projectiles now spawn with different velocities, so they hit the target location at different times.
In testing, with these changes, the mercy was able to kill an unupgraded ACU in 4 hits if the ACU was not moving. However, is the ACU was move away from the mercies, the ACU could reliably survive up to 10 mercies (if it started from full health).
With these changes, the mercy is vastly more effective against stationary targets oh all kinds, can be used against large moving targets and columns of small moving targets. However, it is less effective against individual, small moving targets with high hp.