Introduction to Achron

Achron is a Real-Time Strategy game, with Time Travel as a major mechanic. It is also known as a Meta-Time Strategy game, due to the importance of Time Travel.

As an RTS game, Achron features three unique races:

Humans(CESO), who focus on offense, can spread out easily, but are mediocre in the fields of teleportation and time manipulation.
Grekim, a squid-like alien race that focuses on Time Travel. Its units are highly mobile, and it produces units mainly through other units. All units other than the Gargantuan transport can self-chronoport. It has no teleportation capacity.
Vecgir, a bug-like alien race that focuses on teleportation and modularity. Its infantry units can pilot various vehicles to change their power and abilities. All vehicles can upgrade to self-teleport.

As a Time Travel game, Achron features a completely free-form timeline, which is about 6 minutes long by default. Actions can be performed at any time on the timeline, and are propagated either by the players' observations, or by neutral timewaves. User actions are, however, limited to about 3 minutes in the past (on default settings), but units can be chronoported to the unplayable region, and events can be observed at any point on the timeline.

Beginner's Guide to Achron

Edited from: [A Kron's Guide to Achron]

From a strategic perspective, Achron can be analyzed on three tiers: Linear warfare, Chronological warfare, and Achronal warfare.

Linear Warfare

Linear warfare is the most basic of the three. It is playing Achron in linear time, with no jumping or time manipulation. Essentially, Achron purely as an RTS. In this tier of play, important skills can be applied directly from other RTS games. Since not everyone will be familiar with these skills, a notable set will be described here.

Scouting

Scouting is the most important skill to learn in any RTS game. Knowing what your opponent is doing, and where they are doing it, is the difference between victory and defeat.

In many RTS games, scouting is accomplished through dedicated scouting units. For others, a worker or basic military unit can be used instead. Achron is an example of the latter.

When scouting, the important things to ask yourself are:
1. What have they built thus far?
2. How many Resource Processors do they have?
3. What units are they building now?

These questions are important both for what they tell you directly about your opponent's play, and for what they tell you about what they aren't doing. It is very important to know what your opponent can't do from a given situation, as that will leave an opening for your own play, and will reduce the amount of options you need to consider to counter their play.

Unit Chunkiness

Unit chunkiness is the measure of how much power and resources are concentrated in a unit or group of units. A single powerful, expensive tank is chunky, while a group of cheap marines is fairly divisible.

This is important in two ways. A chunky unit is going to be able to deal more damage over time than a group to a single unit, as damage taken by the chunky unit will not affect their damage output. However, a group of small units is better able to damage multiple units, and to be split up to handle multiple objectives, but will quickly lose damage output as each small unit is killed.

Resources and Production

Resources are the backbone to any RTS game. If you are not gathering enough resources, you will not be able to create enough infrastructure to create a large enough military to defeat your opponent(s). The rule of thumb is: If you can gather resources, do so. Unless spending the resources to create more Resource Processors would leave you vulnerable to an impending attack, build those Resource Processors.

The other aspect of resources is spending them. If you aren't spending enough resources, what you have in the bank is wasted. As a general rule, strive to keep your resources as close to zero as possible. At the same time, don't just queue a bunch of units to drain your resources, as that is worse than having them in the bank. In the bank they can become anything, but when you queue units, now those resources are locked into assets that aren't going to be useful until every other unit in that factory has been built.

Instead, if you find you are unable to spend your resources after building a unit in each production structure, build more production structures. That way, you will have all the resources that you spend on units become useful at the same time.

Another important resource is attention, generally represented as Actions Per Minute(APM). Having a higher average APM means that one is attending to a greater range of events about their base and armies, which can be often necessary to execute various strategies, depending on the game. In Achron, this attention is more useful for unit production than unit control, but they are both important.

Chronological Warfare

This tier is focused on the basic type of time travel in Achron: RTS, with the ability to affect the past arbitrarily. The main difference from the last tier is that actions have a less strigent casaulity. Actions can be undone, orders can be changed, and what you see your opponent do is simply a possibility, rather than a certainty.

This tier introduces the concept of Chronoenergy, which limits the number of actions taken in the past. Its costs are directly proportional to the number of units and the distance from the present.

(Un)Scouting

In this tier, scouting becomes both easier to do, and less helpful when done. Because one can simply issue a scouting order right before a timewave comes, that timewave can propagate the order, while the player is free to undo that order entirely. As a result, you can scout what your opponent is doing without, ultimately, risking a unit.

On the other hand, your opponent can change what they are doing as a response to being scouted. In this way, it becomes impossible to be completely certain what strategy your opponent will ultimately pursue.

That being said, the execution of your opponent's strategy is going to be visible to you, often while there is still some time to adapt to fight it. While careful manipulation of timewaves and careful usage of the past can make this harder, it is still useful to know and an important consideration when attacking or maneouvering.

A useful tool to help determine what your opponent(s) is ultimately up to is by looking at the timeline. All players have a bar representing when they are, which can hint to changes being made. Following other players in time, especially those involved in any battles, will make it easier to determine what they truly have planned.

Unit (Un)Chunkiness

In addition to considerations of chunkiness as a measure of a group's ability to be split up or to withstand damage, there is the concept of chunkiness as a measure of a group's ability to be controlled at various points in time, relative to the present. To elaborate, a large unit built in the distant past requires one order to build, and one order to move, increasing the amount of possible orders that can be given to it and other units. On the other hand, a larger group of smaller units will require more attention and chronoenergy to build and command, discouraging its use in the more distant past.

However, because of the Hierarchies, it is possible to control a large group of units as easily as a single unit, but in the heat of battle, if a commander is destroyed, the hierarchy has to be re-established, which can reduce the orders that can be given elsewhere.

(Un)Resources

This tier puts the traditional concepts of resource collection and spending on their heads. The most easily spotted change is the aforementioned Chronoenergy, which inverts the concept of attention. Instead of attention, that is higher APM, leading to a more effective and coordinated army, it leads to an inability to affect the past deeply.

As an aside, this only holds true for the past. In the present and future APM is as useful as in any other RTS game. That being said, much of an Achron game will involve both players in the past, especially at this tier.

The other aspect that affects attention is the mutability of the timeline, and the freedom to move through time at varying speeds. While this doesn't directly invert attention, it does modify it somewhat. Instead of having to perform many actions per minute in real time to accomplish goals, one can use the pause and slowmo functions to perform many actions per minute in game time, while operating at a relaxed pace in real time.

As for the in-game resources, the ability to move freely through time and attack in the past means that one's Resource Processors are not necessarily as safe as they seem. Your opponent can attack your Resource Processors after you've spent the resources they've generated, leading to units and buildings being un-built. This is known as Chronoterrorism.

Because of the possibility of chronoterrorism, it is not as bad of an idea to keep some resources in the bank. This way destroyed resource processors will not ruin your military and infrastructure.

(Un)Production

Much like with Resource Processors, contruction units and production buildings can be sabotaged, leading to potentially massive butterfly effects. This leads to several preventative tactics:
-Defend your builders. If they die, any buildings they built, and any units built, resources gathered, or other causal effects done by those buildings are undone. It is also a good idea to teleport units across long distances, so that they can't be intercepted.
-Isolate factories. While it can be tempting and useful to build forward factories, they must be defended well, for similar reasons as above.
-Track degrees of separation from the immutable past. If a unit builds a building, which builds an identical unit to the first, it makes a difference which of them builds any further buildings. If the first building is killed before training any units, the second builder won't exist either, meaning anything the second builder made is undone.

Achronal Warfare

Achronal Warfare, where everything is used. In this tier, we add the Chronoporter. This building, along with the Vecgir Slipgate and the Grekim self-chronoportation, allows for the future to come back and help the past, which must in turn maintain the future. This tier is where the Meta-Time aspect of Achron really comes into its own.

It is important to note that tier 2 is the starting state under default settings on RTS maps, while tier 3 corresponds to later game, when Gate Tech and similar upgrades have been researched.

(Meta)Scouting

In this tier, scouting becomes not only about what your opponent is doing when they are, but about what they are doing at all times. Units and infrastructure produced in the relative future can be just as important as those produced in the relative past, so finding out what they are is necessary. As well, since attacks in the relative future are capable of damaging now relevant infrastructure, it is necessary to find and defend against them, as they can damage units which are needed elsewhen.

While a useful tool in tier 2, in tier 3, observing when your opponent is at any given point in the game is now crucial. The timeline adds a lot of potential space, and knowing when you are at risk and when your opponent is open is critical for victory. Most importantly, the unplayable past can become part of the battle, as chronoporting units can have queued orders for when they arrive, allowing for attacks that are difficult to counter. If an opponent is constantly going to the unplayable past, chances are they are following chronoported units there, and are planning an attack.

Unit (Meta)Chunkiness

The concept of chunkiness takes on an additional meaning in this tier. Chronoports have a flat cost, which means that a large number of small units is more expensive to send through time than an small group of units of equivalent power. As well, excepting chronoports to the future, the tier 2 concept becomes even more important, as the chronoenergy requirements for any order will likely increase after the chronoport. For chronoports to the unplayable past, queueing orders quickly requires a lot of chronoenergy, as the chronoport order cannot be issued from a hierarchy leader, thus reducing the chronoenergy remaining for other orders.

(Meta)Resources

Unlike tier 2, Chronoterrorism in this tier is a lot more viable. Not only can units from the future now help attack the past, but attacking the future can also have lasting effects. All the lessons that needed to be learned to prevent this in tier 2 are now of utmost importance in tier 3, due to how easy it now is to get a large army at any point in time.

Also, the concept of resource buffering is not only useful as a chronoterrorism defence, it is also needed to allow for quick chronoportation. Any chronoport costs resources per unit. Because of this, it is important to balance out production for large armies with chronoportation for advantage at a needed time.

Since there is more going on to affect the past, absolute time is more important. Since any event gradually falls off the timeline, it becomes important once again to be able to react quickly and act rapidly. Being able to just undo things becomes much less of a luxury, and queueing the right orders for the unplayable past requires pausing and being quick enough to avoid having your position in time fall into the unplayable past, thus stopping your queue.

(Meta)Production

Because units are now a lot more flexible in when they can be, they can also be more flexible in when things are built. For example, several Octos can be built, then sent back in time to become Resource Processors. Because the Grekim Resource Processors have most of their cost in the Octo, it costs very little to build them, so even if there are few resources in the destination time, there can be a lot of Resource Processors. Another example is if you have a member of a progen triad destroyed while defending it. Another unit can be sent back to complete that triad to maintain consistency.

For Vecgir and CESO, this tactic would likely exist more as a way to get a unit somewhere unexpectedly, allowing it to build buildings in areas an opponent already scouted. While it would have its uses, it is more limited than Grekim, since Grekim uses units for its infrastructure, and does not have any locality restrictions on chronoporting.

For Other RTS Players

For those familiar with other RTS games, here are a listing of some familiar elements and some differences. For the most part, if a similarity is not explicitly mentioned, assume it is there.

General

There are only a few upgrades for each race, all at a single building.
Resource collectors need not return to a central building to harvest.
Resource collectors will stop harvesting when attacked, but this doubles their health. This allows harassment without killing resource collectors.
Waypointing/action queueing and adding units to selection boxes uses the Control key, not Shift or Alt.
Vecgir and Grekim building prerequisites not only have to exist, they also have to be close to, or sometimes directly adjacent to, the unit producers to be useful.

StarCraft

Resource collection by specific buildings, not workers returning to a central building. These buildings can move.
- The placement of resources will not necessarily be in arcs to encourage centralized bases, since bases need not be centralized.
Units only require their production building and maybe one specific research (Machinery for Humans) to acquire, not one prerequisite building each. Some units for Vecgir and Grekim have a couple prerequisite buildings, which also need to be near the production building to work, much like Terran addons but more flexible.
Similarly, buildings are unlocked only by research, and for the most part are available if their builder unit is available. There is no tree of prerequisite buildings.
There are two builder units for Humans, and three for Vecgir and Grekim.
All technology is unlocked by research at a main building. There are no prerequisite buildings for Humans, while there are for Vecgir and Grekim, it isn't one tech building per unit.
No buildings have existing buildings as prerequisites.
Hierarchies work like the Ctrl-right-click follow system, but are much more visible and useful.
There are enough resources to get a very quick start on production, as opposed to just enough for one worker.
You start with a basic production structure, two builder anti-vehicle infantry and a basic anti-infantry unit for Humans; one of each basic infantry unit for Vecgir; and one anti-air builder for Grekim, with Grekim also getting starting resource processors.
Army size is unlimited, however army growth is limited by Reserves() for Humans. Vecgir have a similar Resource called power() which limits the number of vehicles.
Grekim construction resembles Zerg construction, but without the creep limitation.
Human construction resembles Protoss construction, but without pylons.

WarCraft (series)

Note: Most of what applies to StarCraft applies here.

There are enough resources to get a very quick start on production, much like in WarCraft III.
There are only land and air units (WarCraft II).
There are no neutral hostile units on current maps (WarCraft III).
Grekim buildings can move much like Night Elf buildings (WarCraft III).
Grekim buildings are built much like Night Elf ancients (WarCraft III).

Total Annihilation/Supreme Commander

Resource collecters can move. They are not limited to their constructed location.
Resources do run out, but still require no micromanagement to harvest.
Resources can be spread out in various ways, possibly like TA/SupCom, but map-dependent.
Units are paid for when built, not gradually.
Units mostly only need their respective production building to be built. Once Machinery is upgraded, this becomes completely true for Humans. Vecgir and Grekim require Halcyon Class and a Depot-adjacent Aerial Control Center, or Loligo Class and nearby Spyre respectively.
The Human tier pattern resembles Total Annihilation.
The current victory condition is closest to Supremacy (SupCom).

Command and Conquer

Resource collecters need not return to a central building to harvest.
Units are paid for when built, not gradually.
Buildings may be built wherever, though Vecgir work better by using existing buildings to build other buildings.
Resources are only found it set boxes, not occupying large areas. Resources do not regenerate.
Buildings are built by specific units. Vecgir can build also build buildings from any existing building.
All technology is unlocked by research at a main building. There are no prerequisite buildings for Humans. Machinery (for Humans at least) operates much like a Tech Lab. For Vecgir and Grekim there are both research and prerequisite buildings.
Units don't have a strict Rock<Paper<Scissors system for balancing.
Vecgir infantry will eject from destroyed vehicles, but they can't just take over a vehicle, nor can they switch vehicles.

Command and Conquer: Generals

Resource collecters need not return to a central building to harvest.
There are two builder units for Humans, and three for Vecgir and Grekim.
There are no garrisonable structures.
There are no units that interact with neutral units in special ways.
There are few abilities to micromanage. Otherwise micromanagement for targeting and retreating purposes is still important.
All technology is unlocked by research at a main building. There are no prerequisite buildings for Humans. Machinery (for Humans at least) operates much like a Strategic Center, Palace, or Propanganda Center. For Vecgir and Grekim there are both research and prerequisite buildings.
There is no veterancy for units, and no unlockable player powers.
Vecgir do eject from destroyed vehicles, but they can't just take over a vehicle, nor can they switch vehicles.

Universe at War: Earth Assault

Resource collectors operate like Hierarchy Reaper Drones, except they can't move and harvest at the same time.
Research doesn't have as much of a progression, most of it is available at game start.
Slingshots can be used like Novus flow towers, but they aren't as flexible.
Units and buildings can mostly be built as long as their builder exists. Machinery (for Humans at least) is the only tech needed to unlock units, and Gate Tech is needed for Teleporters and the like. For Grekim, the Adv. Buildings upgrade serves the same role, while Vecgir need individual upgrades for two different buildings. No buildings have existing buildings as prerequisites.

Earth 21X0

Vecgir resemble the Eurasian Dynasty in their base construction methods, though every building comes from a Foundation and they are selected like a unit to be trained, not placed.
Vecgir cannot get out of their vehicles to change pilots.

Relic games

In general, pretty much everything is different between Achron and Relic's games.
You can hear into Fog of War, though you can't get any indication about where that sound exactly is, apart from your ears (Company of Heroes).

Age of Empires (Series)

There are no naval battles.
There are no progressive upgrades. Ground Units (upgrade) and similar upgrades do upgrade some weapons, but units are generally as-is.
There are 4 resources, however only 2 are collected, and the other two are each specific to one race (Grekim has no special resource) and generated from nothing.
It is possible to convert resources. However this only applies to Q-Plasma conversion to L-Crystal, and the conversion is not reversible (it is, of course, undoable).
There are no wonders, or non-military victory conditions.

Rise of Nations (Series)

Note: Most of what applies to Age of Empires applies here

Resources are finite. There are, however, still both resources to harvest and resources that are generated from thin air.
Research doesn't have as much of a progression, most of it is available at game start.
Vecgir build structures from existing ones, like city districts in Rise of Legends.