Rosetta has two main forms. Her humanoid (also referred to as Doll) form appears as a main story and Pain Cage boss, while her quadruped form appears predominantly as a Co-Op (Raid) boss.
Aerial Railgun: Flies into the sky, raining lightning bolts upon her enemies. This attack will strike anywhere from three to five times; its strikes are signaled by a spark appearing on the active player character.
Rising Thunder: Pushes forward with her shield, then rises into the air, releasing electricity.
Spinning Uppercut: Swings her shield, then spins upwards and forwards, dealing multiple hits to enemies in range.
Dive Slash: Leaps high into the air, then dives at the enemy with a pierce and uppercut attack.
Crisis Breakthrough: Thrusts her spear forward, and then follows up with a shield bash. Also known as Forward Thrust.
Shield Rush: Raises her shield and rushes towards her target, blocking damage.
Freezing Storm: Launches three simultaneous cutting projectiles in an arc.
Freezing Wind: Floats backwards and launches a single cutting projectile linearly.
Homing Missile: Launches five homing projectiles at the enemy.
Quad Combo: Performs a 4-hit close-range combo.
Triple Combo: Performs a 3-hit close-range combo.
In both forms, combat with Rosetta is generally unchanging.
Rosetta's attacks largely depend on the distance between her and the player character.
At long range, she will use Freezing Storm, Freezing Wind, Homing Missile, Aerial Railgun, and Shield Rush more often.
At medium range, she will use Dive Slash and Crisis Breakthrough more often.
At close range, she will use Spinning Uppercut, Triple Combo, Quad Combo more often.
During combat, Rosetta will respond to receiving melee damage by backstepping, then performing any of her regular attacks. During most of her attacks, Rosetta will gain Super Armor.
The main exception to this is during Matrix. During this time, Rosetta's Super Armor will be disabled, and she will not backstep when taking damage. This period of time will often extend a few moments after Matrix, as well, to allow the player to finish their combo.
She will also remain stationary during most Signature Moves.
If the player continues to deal melee attacks to her despite her backstepping, she may continue to backstep further. There is no limit on the number of backsteps Rosetta may perform, but she will always break the chain with an attack of her own eventually.
When receiving ranged damage, Rosetta will frequently respond by executing a Shield Rush. She will gain Super Armor and rush forwards towards her target, executing any of her close-ranged attacks once she enters melee range.
Upon the release of Firn Night, this enemy received a sprite renewal.