The boss of the game isn't playable in the arcade version without hacking it, but both of his forms are playable in the Dreamcast and Playstation versions. However, the playable versions are toned down compared to the CPU controlled version you fight in arcade mode, as several of his moves have been made into hyper combos, and Onslaught now has a hyper combo gauge (the arcade mode version doesn't have this, and can do any move whenever he wants).

SENTINEL FORCE
(P or K)

A couple of small Sentinels will fly across the screen and drop bombs on the opponent.


HYPER GRAV
(F, D, DF+P)

Onslaught sends forward some energy spheres which cannot be blocked! If they hit the opponent, they will be dragged back right in front of Onslaught for a couple of seconds.


MAGNETIC TEMPEST
(QCF+P)

Onslaught creates and then sends forward lots of projectiles.


ONSLAUGHT HEADCRUSH
(QCF+K)

Onslaught will charge forward and ram into his opponent.


TELEPORT
(QCB+K)

Onslaught will vanish, then appear again a little distance away from his opponent.


SENTINEL CHARGE
(SP+FK)

A Sentinel will dash across the screen and smash the opponent out of the way.


HYPER COMBO
HYPER MIND BLAST
(QCF+PP)

A gigantic laser blast.


HYPER COMBO
MAGNETIC SHOCKWAVE
(QCF+KK)

Onslaught creates several shockwaves that hit one after the other.


LEVEL 2 HYPER COMBO
MIND CONTROL
(QCB+KK)

Onslaught will teleport to the background, and take over the mind of a random fighter to do his fighting for him! The CPU controls the mind controlled fighter, who has a vitality bar which is one quarter full. In the Playstation version, the mind controlled fighter will be a clone of your opponent.

If you are playing as Onslaught's first form and lose, it isn't over yet as you will get to then use his second form. Again, this playable version is weaker than the version you fight in arcade mode, as the hyper mind blast is now a hyper combo. The arcade mode version can do this move whenever he wants.

CLAW SWIPE
(P)

Onslaught will swipe at the opponent with one of his hands.


SENTINEL FORCE
(K)

A couple of small Sentinels will fly across the screen and drop bombs on the opponent.


MIND BLAST
(QCF+P)

Onslaught will fire a single laser shot that creates a large explosion when it hits the ground.


BEHOLD MY MIGHTY HAND
(HCF+K)

Onslaught will dash back, then rush forward and swipe at the opponent with one of his hands.


HYPER GRAV
(QCFx2+P)

Acts the same way as before. These projectiles cannot be blocked and will drag the opponent below Onslaught's head if they hit.


HYPER COMBO
HYPER MIND BLAST
(QCF+PP)

Onslaught will shoot several lasers across the floor, each one causing a huge explosion.