alias: Group_battle -> battle

Alias group_battle -> battle

reason: with the new definition of battle and fight, the former is now redundant since a battle has to be more than a one on one.

Unless it can be changed to mean a battle between two defined goods (red versus blue, good versus evil, or any two (or more) factions against each other).

I think an implication works better.

Decided to change the definition to what was in the latter sentence in the end.

Implication already existed.