Dark Bomb is a dark power used by Dark Jak during Jak II and Jak 3. Dark Jak gains control of the power after bringing 25 skull gems to the oracle at its hut in the Water Slums in Jak II. The oracle helps control his new-found powers, a result from Baron Praxis' dark eco experiments. In Jak 3, the game allows you to use Dark Bomb after the second mission.
Combat[]
Dark Bomb.
Dark Bomb is a very powerful attack activated by pressing 
+ 
(normally a dive attack). During this attack, Jak jumps into the air and drives his fist into the ground, releasing a powerful, large-radius shockwave of dark eco, destroying enemies within its proximity, sending them flown back a large distance. Dark Bomb is most useful during ambushes, large-scale engagements, or boss enemies such as Baron Praxis or Metal Kor (however, Dark Blast is considered more suitable for more massive enemies as it is an airborne attack opposed to a ground-level attack).
When activated, the game screen slows down, displaying the large amounts of dark eco bolts impaling nearby enemies and blasting them away. After performing the attack, Jak's dark eco meter gets entirely depleted. In Jak II, Jak's meter must be completely full, whereas in Jak 3 Jak's meter must only be mostly full.[nb 1]
Attack the robot guard[]
If you use a Dark Bomb in a body of water that is under the surveillance of a robot guard, the drone will disappear, allowing you access to the normally-restricted open waters. Be sure that you perform the attack the moment the drone appears, as it can still kill you in a single shot. It is unknown what exactly happens to the drone, as it does not appear to get destroyed and apparently just sinks back down where it came from. It is unclear whether or not this was intended to be possible or is simply a bug.