Heihachi is an offensive Mishima that boasts powerful mids, high damage, and oppressive pressure.
In order to get entice his opponents to get hit by these mids, Heihachi also possesses powerful lows. There is a caveat however, as having one of these lows blocked will often cost you the round. Luckily, Heihachi has a variety of options to press his advantage, and he can use these situations to gauge your opponents tendencies.
Even in a large life defecit, Heihachi is always a threat to take the round, especially in Rage.
Like other Mishima-style characters, Heihachi demands fairly high execution to be played to his fullest potential, although he isn't as reliant on the Electric Wind God Fist as Kazuya.