Cyclic and chain quests

OP-2 has cyclic and chain quests, which are quite isolated from the rest of the game, and only needed for three things:

* Rewards
* Reputation (1-3 rep for each cyclic task; affects trading and charging prices)
* Achievements

"One-time cyclics" (for the lack of a better word) are also used to purge quest item leftovers the player might have after certain quests.

## Cyclic quests

Certain NPCs have repeatable (cyclic) quests, marked blue in the dialogue. Tasks of the same type (fetch an artifact, kill a stalker, etc) are grouped into tiers that have progressively better rewards. Certain events like plot progression and unlocking new locations make NPCs offer more advanced tiers.

Current tier resets to the basic after 5 days of not accepting the next one. Cyclic tasks have a deadline of 14 days, so before accepting one make sure you can complete it in two weeks.

If you fail 10 cyclic tasks, you'll get a negative achievement and all further cyclics will be blocked for you, as well as the main achievement of the game.

Some cyclic tasks are not actually repeatable and just offer a reward for certain useless items so players don't keep them around wondering what they are for.

### Assassinations

Sometimes you'll get contracts on killing neutral or friendly stalkers. You can do it in several ways without wrecking your reputation:

* Indirect explosive damage. Blow up a red barrel near him, or a Gas canister, Colloidal gas cylinder, a mine or any other explosive. Making him step on your mine or into an anomaly created by you doesn't work, as it still counts as damage dealt by you.
* Sell him a remotely controlled explosive, and blow it up with a remote detonator.
* Push him into an anomaly with a physics object in your hands, such as a crate.
* Lure mutants to him
* Just wait for him to die. Sometimes works for the camps that are get raided regularly, like stalkers at Agroprom.
* Drunken Master style™. Get high on psi (drop your psi health to 10% or less), and you'll become zombified for approximately a minute. Every stalker around will turn hostile temporarily, and you can murder them in cold blood without repercussions. Good luck doing so while high, though. You can get high by dropping and picking up any artifact that gives a psi shock, for example Sea Urchin. Don't do it while naked though, as it will spawn a lot of insects. Be sure to not do it at the Freedom base at Army Warehouses, because they seem to be especially touchy about player changing factions, and will become permanently hostile quickly. This is not true for other Freedomers, such as those at the Barrier.

### Wandering enemies

Sometimes when you accept a camp cleanup cyclic, enemies can wander off the marker quite a bit, and it can be hard to determine which enemies you have to kill for the cyclic to complete. This is true for mercenaries at Ironworks, and zombies and the controller in the Darkscape, but also some other camps. Remember them and ignore these cyclics if you don't like this.

## Chain quests

Most essential NPCs also have a one-time chain of fetch tasks, usually the last one in the list. Those are special and don't have any deadline. The chain can be quite long and sometimes require unique items only obtainable at certain points of the game. At the end of each chain, you receive a reward (often really good or even awful) and an achievement.

## One-time cyclics

Some NPCs have one-time tasks that aren't chains. Their main purpose is to purge quest item leftovers the player might have after certain quests. For example, Informant will request you to bring many quest-related notes and PDAs you might have left from progressing the game. This also stops players from wondering whether they need this item later; if an NPC asks you for it in a cyclic, you won't need it anymore.

However, there are also some "one-time" cyclics that are used for other purposes. For example, Adrenaline's offer that lets you have a Moss early on.