For example, in some studies a drug was given to people which blocked the effect of endorphins. These people still felt the runner's high; it means this feeling is not caused by the release of endorphins in the blood. Another study was performed in 2004, which showed this feeling is related to a different body chemical named "anandamide". is not an endorphine but is an endocannabinoid, similar to one of the chemicals in marijuana and chocolate.
Team Fortress 2
Team Fortress 2 is a free-to-play multiplayer first-person shooter video game made by a company called Valve Corporation.
The game has nine characters, called classes, and two teams that battle each other in many different ways, like Payload, which has one team pushing a cart along a track while the other team tries to stop them, and a twist on capture the flag where instead of a flag players must capture a briefcase with important papers. The game is set in 1968, in an alternate history. The game is also inspired from many famous Spy Movies and TV shows, taking elements from James Bond, The Man from U.N.C.L.E, and Get Smart.
The game was first released in October of 2007 in "The Orange Box", a package with "Half Life 2", "Portal" and "Team Fortress 2". It was later released separately for the Playstation 3, Xbox 360, Microsoft Windows, Linux and Mac computers. It became free to play on June 23, 2011.
"Team Fortress 2" has nine classes. The classes are split into groups of three, which are offense, and support. Each class has its own strengths and weaknesses, causing the classes to rely on each other to win, promoting teamwork. Also, each class can change their weapons to different ones that they find over time or make from scrap metal. For example, the Soldier could change his normal rocket launcher into 'The Direct Hit.' It shoots faster, stronger rockets at the cost of having a smaller explosion size. In general, the different weapons are not upgrades, but rather 'side-grades.' They are better at certain times, while worse at other times.
The offensive classes are the "Scout", the "Soldier", and the "Pyro". These classes have abilities that make them best suited for attacking the other team, but also easy to kill.
"The Scout" is a young man from Boston with an interest in baseball. He is the fastest runner in the game, making him a good class to use in capture the flag, as he can run in, grab the enemy team's briefcase, and run out. Also, he captures control points at twice the speed of any other class. However, he also is tied for the lowest health of any class. His default weapons include a scattergun, a pistol, and a baseball bat. He is excellent at killing Medics and Demomen.
"The Soldier" is a middle-aged man from the American midwest. His main weapon is a rocket launcher which he can use to blow up enemies, or, if fired at his own feet, can be used to make him jump very high. This is called 'rocket jumping.' Rocket jumping will hurt the Soldier, though, and if he is low on health, it could kill him. Rocket jumping can also make the Soldier move forward very fast, sometimes even faster than the Scout. Soldier also uses shotguns and shovels to attack. The Soldier is a good offensive class but he cannot move very fast and is easy to hit. The Soldier has a large amount of health, the second highest of all the classes.
"The Pyro" is a character wearing a full-body rubber suit and gas mask, so nobody knows their race, age, or gender. They also speak in a muffled voice so nobody knows what they're really saying. Pyro's main weapon is a flamethrower, used to set enemies on fire. Once an enemy is set on fire, they will burn for several seconds, meaning they can die even if they have killed the Pyro that set them on fire. This is called "Afterburn". For backup, they have a shotgun and a fire axe. The Pyro is good for checking for Spies using their flamethrower. This is called "Spy-checking". Pyros can help against Übercharged players by pushing them back with an "Air blast" or "Compression blast". The air blast can also reflect projectiles, such as grenades or rockets, back at the enemy team, which will inflict bonus damage. They are weak at long range. The Pyro has a good amount of both health and speed.
The defensive classes are the "Demoman", the "Heavy Weapons Guy", and the "Engineer". The abilities of these classes make them best for defending things their team needs, such as control points, briefcases, and carts.
"The Demoman", short for Demolition Man, is a black Scotsman with an eyepatch. His main weapons are a grenade launcher and sticky bombs. Grenades will explode immediately if you hit a player before the grenade hits the ground, or a few seconds after being shot if they do not hit anything. Sticky bombs can stick to walls and then be set off by the Demoman when an enemy gets close. The Demoman can also replace his sticky launcher for a shield. The shield lets the Demoman charge forward at high speeds, and do more damage with his close-ranged weapon. His close-range weapon is a bottle of whiskey. The Demoman is a very strong class. His sticky bombs do great damage, and can be used to 'sticky jump' much like how a Soldier can rocket jump. Also like the Soldier, the Demoman is good in most situations. He is an easy target for Scouts, however.
"The Heavy Weapons Guy", also known as the Heavy, is a middle-aged man from the Soviet Union who is built like a tank. Because of his large size, he has the highest health of all the classes. Also because of his size, he is the slowest runner. His main weapon is a minigun which he named Sasha and treats like a person. The minigun does by far the most damage at close range of any gun in the game, due to its high fire rate and damage. It uses a lot of ammunition very quickly, so if he runs out, he can use his shotgun or his fists to punch enemies to death. The Heavy is great at close range or in small, cramped places. Spies and Snipers are useful for killing Heavies because they are capable of doing high damage instantly with backstabs (Spy) and headshots (Sniper). At close range, the Heavy will usually win one-on-one fights unless he is surprised.
"The Engineer" is a middle-aged man from Bee Cave, Texas with 11 Ph.D.s. His main use is to make buildings. His first building, the Sentry Gun, is a non-moving gun that targets enemies and shoots automatically. It can be improved to have more health and firepower. His next building is the Dispenser, which gives his nearby friends health and ammo. Finally, he can also build teleporters, which can move his friends closer to the fight. The Engineer also has a shotgun, pistol, and a wrench to defend himself. His Sentries are great for stopping anything short of an Übercharged player. The Engineer himself is weak, and poorly placed Sentries can be blown up by smart Soldiers and Demomen. Spies also ruin the Engineer's day.
Finally, the supporting classes are the "Medic", the "Sniper", and the "Spy". Their abilities are there to help the team, so they do not typically engage in direct combat, but can if they must.
"The Medic" is an older man from Stuttgart, Germany. His main duty is healing the other classes. He has a machine called the Medigun which, when pointed at a teammate, slowly restores their health. He can also 'overheal' players, which gives them more health than they can normally have. This overheal slowly fades over time. After healing for a few minutes, the Medic is able to use an Übercharge, which makes him and his heal target invincible for a few seconds. For defense, the Medic has a bone saw and a gun that shoots syringes. The Medic is a very powerful teammate, but is easy to kill at the same time. Since he loses almost every direct fight, he usually stays with a teammate who he heals, called a 'Medic Buddy' or 'Pocket.' This Pocket player's job is to keep the Medic safe. The Pocket is usually a Heavy, Soldier, or Demoman due to their large health and firepower.