Here's the scenario, involving The Only Game That Matters (Any phase: until the end of the challenge, participating characters do not count their STR.)
1) opponent attacks with a Carrion Bird (MIL, str 1). I play The Only Game That Matters, and declare no defenders. Have I won on defense?
2) opponent attacks with a Carrion Bird (MIL, str 1), I defend with a Carrion Bird (MIL, str 1). I play The Only Game That Matters. Have I won on defense?