To start off, the player has a given number of hearts (1 to 4+) which go away one at a time from any successfull enemy attack. There is a very small period of invincibility after getting hit. The only way to regain health is at the safe zones along the way.

The enemies, on the other hand, have a health system where they can take multiples attacks without dying, and if you give them time to recover, they regain health. Thus, focusing on attacking one single enemy, except in special situations, is paramount.

Ninja Default Hit
There is currently one attack in the game that requires four hits to kill an enemy, and that is the Ninja's unarmed strike.

Unarmed Combat
The standard amount of hits required to kill an enemy is 3, for Testmind, Addict, and Dog. By default, Dog can have his charge count as one hit as well.

Thrown Items
I did not appreciate how many thrown items there were in this game until I went looking for them. As a general rule of thumb, if it looks like if you threw it and it would hurt without killing, it will do 1/3 damage to the enemy; thus three items need to be thrown. Some such items are: wine and beer bottles, coffee cups, plates, vials, computers, skulls, vases, lunch boxes, cinderblocks, minature trees, office supplies, bones, radios, building models, art supplies, desk trinkets (including a dinosaur!), suppliment bottles, gas and oil cans, gas station hotdogs, cameras, portraits, billiard balls... and any empty firearms thrown at your enemy as well.

Addict Upgrades
The Addict mind can be upgraded to only require 2 hits to kill an enemy, as well as only 2 thrown objects.

Firearms

Pistol
Fires 1 shot, then requires a reload. Medium amount of ammo.

Automatic Rifle
Fires 1 to 4 shots, requires no reload. Largest amount of ammo.

Shotgun
Fires 1 shot with around 7 or 8 pellets, then requires a reload. Very low ammo.
This is the only firearm that can be used as a club when empty, for now.

Fishgun (Sniper)
Fires one extremely fast shot, then requires a reload. Medium-low ammo.

Melee Weapons

The following held weapons kill enemies in one hit: Baseball Bat, Pipe, Katana, Crowbar, and Shotgun.

Piercing Thrown Weapons

The following weapons kill in one hit when thrown: Credit Cards, Collapssable Fans, Knifes, Post Cards, Archeologist's Tags, CD's, Katanas, Shuriken, Cleavers, and Disk Folders.

Mind Upgrades

Addict can be upgraded to kill any body that he hotswitches out of. It can additionally get an upgrade to chain hotswitches.

Dog can be upgraded to kill during a charge attack. It can be upgraded to chain charges as well.

Ninja
Ninja can be upgraded to have his thrown Katana pierce through multiple enemies. Additionally, when he recalls his sword, it can kill multiple enemies. On top of that, he can be upgraded to have his thrown Katana seek out enemies when recalled. I have seen it kill three enemies when recalled with that upgrade.

Picture provided by Flickr user "Yau Hoong Tang" at https://flic.kr/p/7Pr9k2

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