Blink

Whoever talks first loses.

Is silence one of the oldest tactics (games?) in the book? Probably. Shortly after people started to grunt, they started to understand the power of refusing to speak. Lips sealed tightly, head averted so even a nonverbal signal is denied, words pinging through the mind and not being allowed out through the clenched jaw.

Whoever caves first cares most, wants more, needs more, is weaker, more vulnerable, has less power, or maybe is just admitting their fault.