Intel

Achron has Fog of War that limits what parts of the battle field are visible to each player. There is an option to turn it off. Each unit class has a sight radius that determines how far into the fog the unit sees. Sight is not directional but it is affected by line of sight.

Not all information about enemy units are seen. Health is but information about energy or ammo status is not.

The main way to keep oneself up what the current game state is to have units witness events. Units with high movement speed are able to quickly take a peek anywhere desired such as Lancer, Shin Pulser, Sepipod. Comm Center has a large vision radius making it easy to observe a large surface area.

Units can also be cloaked. Cloaked units can only be detected by detectors. A unit that is unseen cannot be directly fired upon. They do receive splash damage and their position can be attacked, but units don't automatically seek them out. Units can fire from cloaking while remaining cloaked.

The information gain from witnessing doesn't limit to the thing seen only. Guesstimates can be made about the likely consequences and reasons for what was observed. For example a lonely trio of an octo, pharo and sepi is very likely to progenerate more units and establish a base. Similarly if a player has made a lot of heavy tanks it's required that he has researched machinery at some point before that.

Because timelines change only in small increments changing location of the witnessing event can provide more information for very small reliability losses. Even a sinle unit might be enough to query the whole configuration of the opposition if the scouting trip is redone repeatedly. However because timelines do change information gets old. Even if the player has seen something with his own eyes a later timewave might wipe this event out whether or not the player is there to see it. Thus it might be important not only to see what happens but does it happen (and when it ceases to happen if it does).

Because players make their decisions based on what they know about the timeline it might be advantageous to make the timeline seem a certain way to elect a specific response from the opponent. It helps that contents of the timeline can be rectified, meaning that things done only for appearances need not mean nothing about the final configuration. However because chronoenergy and commanding attention is finite the more past an event is the more likely it is that it remains so.

Also the cost of obtaining information must be taken into account. A simple scout mission in the present is very likely to tell the opponent that you are aware of information obtained this way. However if one is only interested in unit types produced it might be advantageous to make such a scouting trip in the future and infer what is the present composition. This way the same information is less likely linked with any attack plan in the present.