The following is a procedure for theater of the mind or non-grid based combat with simple, non-defined ranges. It is not limited to fantasy genres.
Players have two Actions during their turn. They can use one Action to Move from one Cluster to another. (Some games have their own Movement and only one Action; in games like this, use your Move action to move form one Cluster to another. Adjudicate attacks of opportunity if your system has them.)
You can use your Action to Attack any enemy within the Cluster. Ranged Attacks can hit enemies in other Clusters. However, if an ally is also in the Cluster, Ranged Attacks will have Cover. If your game has multiple cover options, each successive ally in a Cluster ranks Cover up to the next. (For example one ally may provide ½ cover, two allies 2/3 cover, etc.)
AOE Actions (such as spells, grenades, etc.) affect all participants in a given Cluster. If your game has particularly large AOEs, then it may envelope two or more Clusters, based on the relative size of the AOE and how large the battlefield is.
The advantage to this is that it’s easier to remember what players are attacking what Monsters in a given Cluster and makes it easier to adjudicate AOEs in theater of the mind.
