Warfare is a strong option for learners who already feel comfortable with English and want a more demanding challenge. Following the story requires attention, so language difficulty is not the only challenge here. The vocabulary is not overly technical, though it includes enough variety to make the practice meaningful. At around 70 words per minute, the rhythm of the dialogue is manageable and easy to follow. It should work best near B1/B2, especially for learners prepared to handle a more complex story.
