Convert the last of the three existing Lua AIs in 'Guardians' (return guardian, stationed guardian or coward) to a Micro AI and document it on the Wesnoth wiki. This should be done as a parametrization of the existing guardian Micro AI, rather than by creating a separate Micro AI.

This task requires tasks Micro AI 'Guardian' Step 1 and Step 2 to be completed first.

Examples of two micro AIs already exist and can be used as models for this task. Documentation about Micro AIs in general and detailed instructions for this task are available on the Wesnoth wiki.