How do you parry in UFC 6?

High block and lean the head back. It is a timed perfect block on head straights, not a hook catch.

Can you parry an overhand?

You should not. Overhands are built to punish the pull. Slip outside or duck.

Only when you have read the straight or your block meter is dying. A guessed parry is a clean shot for them.

A parry is a timed perfect block on a head straight. Miss it and you eat a clean shot. Land it and you get a short counter window.

How the UFC 6 parry works: block and lean back on a straight, when it saves a broken guard, and why overhands punish it.