Martian Officer

Officers appear during Martian Madness and nowhere else. That means Golem has to be down first, and a Martian Probe has to scan you and get away to start the invasion. They never wander in on their own outside the event.

Every officer arrives wrapped in a Bubble Shield, and while that bubble holds, the officer inside cannot be hurt at all. The bubble also cancels knockback and shrugs off lava, so an arena built around pushing enemies back or dropping them in a pit does nothing here. Pop the shield and you get a window of about three seconds. Miss it and the bubble returns at full strength, though the damage you already put into the officer stays gone. Nothing about the shield changes in Expert or Master, which makes it one of the few things in the game that behaves the same at every difficulty.

The officer has no attack of its own. It is a support unit that keeps itself standing while the rest of the invasion shoots at you, which is exactly why leaving it alive is a mistake. Bring burst damage rather than steady chip damage, because slow sustained fire just loops the shield cycle forever and you never reach the body underneath. Weapons that pierce or splash help, since the bubble and the officer are separate targets in a crowded fight. It is worth hunting rather than dodging: some of the better weapons from the event come off officers.