For Galvek, switch from ruby to diamond bolts when his HP is roughly around 300 HP or about one-third to two-fifths remaining. The forum consensus in the results points to ruby being stronger early, then diamond taking over once the ruby proc value drops off.

Practical rule

  • Use ruby bolts at the start and through the early/mid fight.
  • Swap to diamond bolts once Galvek is around 300 HP.
  • Some players also describe the switch point as around 35%–40% HP , or anywhere from 250 HP down to 200 HP depending on gear and ranged level.

Why that works

Ruby procs deal a percentage-based hit, so they’re best while Galvek still has a large health pool. Diamond bolts become better later because their defense- ignoring effect gives steadier damage when ruby procs stop being as efficient.

Simple rule of thumb

Ruby early, diamond late.

If you want the safest one-line answer: switch at about 300 HP.