Hopefully this is what you meant be specific example: 

In turn.rb I create a turn with 2 Fighters. These fighters already have moves assigned on creation.
1) I need to assign a specific move and ranking for testing
Next, Turn randomly chooses a move for each fighter.
2) I need to assign a specific move to each fighter so I can test that the right move won

Are you saying I should have created a method #random on Turn that took 2 Moves so that when testing I could send in the Moves I want?