With no upgrades, holding down the attack button will make Mondo charge up for a Spin Attack. Upgrades will increase the number and speed of spins and add a finisher where Mondo leaps into the air and slams the ground with his katana, causing a huge shockwave that greatly damages any enemy near him.
One of the Musselback's optional alternate modes is the Charge Cannon, which is a much more powerful, chargeable blaster.
An optional upgrade for the Musselback is a charge punch, which will break a guard in one hit.
Continue Your Mission, Dammit!: Kind of. Throughout the game, the various beauties that Mondo has a Gigolo mission available for will call him in the middle of missions to remind him to go see them. Played with in the sense that the Gigolo missions are entirely optional. It doesn't make it any less irritating though, when the same beauty can call you three times in one episode, sometimes even with the same quote!
Counter Attack: Dodge Burst, Counter Smash, and Counter Shot. Counter Smash works after doing a Just Guard (pressing block when a Wire flashes red) and pressing the button prompt that appears (Y on 360/Triangle on PS3). The Counter Shot works by doing a Dodge Burst on gun wielding Wires. The last two counters you have to buy with your upgrade points.
Downer Ending: After spending the entire game fighting off the corruption within his arm, Mondo is corrupted at the last second by David's blood and becomes evil. The ending shows what seems to be his profile from the back repairing David's wrecked mansion with immense dark powers, both arms restored.
Elite Mooks: First, you have your basic, unarmored Wires. Next, you have your gold-armored ones that can take more damage. Afterwards, there are the hardier and more vicious enemies that wear headdresses. Finally, there are the Wires that are protected by a high-class alloy who can only be killed via Adrenaline Burst decapitations.
Finishing Move: Lots of them. The aforementioned Counter Shot always kills any Wire in a single hit as it's an automatic head shot and Adrenaline Burst can be use to instantly kill any non-protected enemy and is often used to finish off stronger ones when you damage them enough. There's also Judgement, which becomes available when you kill an enemy with maximum sword level and allows you to pick which type of Power-Up they drop afterwards, with a different animation for each one that also varies depending on enemy size.
If You Kill Him, You Will Be Just Like Him: A major plot point is how killing Wires and Execution Targets releases varying quantities of Dark Matter. Most of it is sent to the Moon but a good quantity of it engulfs the general area, possibly infecting everyone therein if they aren't adequately shielded. Large levels of infection result in the afflicted gradually turning into Wires, gaining vast physical enhancements, but ultimately robbing them of their humanity.
Laser-Guided Amnesia: Mondo doesn't actually remember getting his cybernetic arm. He also doesn't remember Takeru that well.
Magical Realism: An excellent example, demonstrating all the hallmarks the genre has in other media. The world is populated by various supernatural effects from mad science to aliens that mystify some but are treated casually by most others. The magic provides the setting for the physical and emotional conflict but is in itself merely a part of the natural world. Therefore, the nature and details of the magic are mostly assumed as background and mood without interrupting the story.
One instance occurs at the end of the mission with the giant that somehow "stole the world", even though the level takes place in America, on Earth. At the end of the level, Mondo actually finds a scaled down but otherwise perfect and realistic replica of Earth. Aliens arrive and also "steal Earth", leaving behind a similar model of the sun instead. Even though it's patently impossible, the implication is that those globes were the actual Sun and Earth. The world Mondo is on is completely unaffected and everyone seems to accept what just happened at face value without caring much, but all the characters have a sense that there has been an immense change or paradigm shift (the story is shifting into the endgame at this point, and Wham Episodes are imminent) as if the Earth has been shaken, figuratively speaking. Yes, this is perfectly exemplary ofMagical Realism.
Osama bin Laden: Mondo was one of the assassin's responsible for the killing of his world's Osama Bin Laden. The resulting evil energy released from killing him infected Mondo's teammates and his arm, resulting in his need to have it altered into a bionic one.
Power Limiter: The upgrades for Mondo's katana, Gekkou, involve removing these: the more limiters are removed, the higher the katana's power will increase with higher combos and the less hits it takes to reach lower power levels. In gameplay terms, this translates to more damage and more elaborate combos, with lv4 adding glowing blue Sword Lines to all of Mondo's strikes and lv5 changing most of his attacks to elaborate flips.
Retired Badass: Bryan has retired from carrying out executions in the field, but still runs the agency (and will occasionally help Mondo out).
Scary Shiny Glasses: When he's wearing them, Mondo's glasses are almost always reflective to the point of looking opaque.
Sealed Evil in a Can: The Moon is a giant repository of the Earth's evil energy that is only kept in check by several massive blood gems.
Serial-Killer Killer: An assassination agency (state-sponsored, mind you) that only targets killers, hence the name of the game.
Shout-Out: When confronting Hamada-Yama, Mondo tells him that he became an executioner because he woke up one day with a mechanical arm. Hamada responds that it's a good thing he didn't become a poisonous insect.
The vampire Sebastian from the DLC mission turns into a demon that greatly resembles Dracula's final form from Castlevania: Bloodlines, with the main difference being that his torso consists of an entire face instead of just the crotch-mouth and he has an additional pair of wings.
One of Scarlett's hiding spots in Mission 7 which takes place in Japan is inside a glowing stalk of bamboo admidst a field of them, much like Princess Kaguya in the old Japanese story Tale of the Bamboo Cutter.
Unicorn: One appears throughout the game. Its name is Takeru. He claims Mondo is his master.
With Great Power Comes Great Insanity: Becoming a Wire makes you pretty powerful, ditto if you were pretty strong before you got turned into one. However, the evil energy will corrupt you, robbing you of almost all sense and empathy.