Welcome to The Thrill of the Fight!
This brief guide is intended to help beginners get started. For a more detailed treatment of game mechanics, please see the official guide the developer wrote. In case of any discrepancies between the guides, obviously his guide is correct and most up-to-date!

Thrill of the Fight is a semi-simulation--it is the most realistic fighting game in VR at this time. This means that much of what actually works in boxing works in this game. If you practice your technique, it's even a pretty good supplement to boxing training. It is also an amazing workout (VRFitness insider scores it as burning 900+ calories in an hour of play time!).

Setup
The game takes the play area you defined when you set up your VR system and shows it as a red outline on the floor. The red outline should match the green rectangle shown during SteamVR room scale setup or should be the largest forward-aligned rectangle that will fit within your Oculus Guardian outline. If you haven't set up room scale mode for your VR system, you will be shown a 1m by 1m square (which is just a fallback - the game requires a 2m x 1.5m / 7ft x 5ft minimum play area size set up in room scale mode to work properly). All of the fighting action takes place within this red outline, and the opponent is immediately moved inside of it when the round starts and will not leave it. It's important that you start the round from back in your corner with the menu in front of you in order to make the most of your play space.

I recommend you set up your controllers so they are facing outward. This minimizes the chance that your controllers will hit each other.

Beta Branch
The developer uses the Beta Branch to test out new options. This is where the new stuff gets rolled out first. To activate it, go to your Steam libary, right click on The Thrill of the Fight, go to Properties, Select the Betas tab, and activate Beta in the drop down menu. It will do a pretty quick re-install. If it is giving you any problems, you can easily roll it back by repeating those steps.

You are not chipping away at a health bar like in a traditional fighting game, but are trying to land a powerful blow to bring your opponent down. Technically your very first punch in a match could be a knockout punch if you land a hard enough hit to the right spot.

The closest equivalent to a health bar is what the developer calls the "trauma" system. The more damage you do to an opponent, the more they'll be affected by your future punches. The damage increase is extremely small, but it adds up over time and makes knockdowns more common in later rounds than earlier ones.

You can score knockdowns in two ways - either by knocking their lights out with a hard, well-placed hit, or by dizzying them with a series of less-hard or less-well placed but still hard hits. Dizzied opponents get wide-eyed and have trouble focusing their gaze on you, and they'll recover after a few seconds if you don't follow-up with more hard punches. This dizzy system works the same way for the player. When you get the blurry double vision, that means you're dizzy and at risk of dropping if you continue to take hits.

Once you knock them down, the chance of them getting back up or not is determined by how hard the blow was that knocked them down.

A "hard" punch is hard relative to your punching strength. The game automatically adjusts your punch force to try to make your hardest punches equal to the hardest punch that makes sense for game balance. Punch at a force you find comfortable (don't over-do it) and the game will adjust to you. Make sure the faster swings you throw are the ones you're trying to make count and aim them at weak points for the best results. Throwing lots of weak punches will generally tire you out and will not help you much.

Focus on going for your opponent's weak points, including the sides of the chin, under the chin, the temples, and the solar plexus. In the current version, the opponent will grunt if you hit them with an exceptionally damaging punch. This doesn't exclusively mean you hit a weak point, but it's a good indicator. It takes some practice to reliably hit those spots. There is a practice dummy in the gym that tells you when you hit a weak spot.

The game is more of a simulation and is meant to go to the scorecards for three-round bouts. The developer aims for about one knockdown per round between you and your opponent - maybe 4 or 5 total in a three-round bout, with knockdowns becoming more common in later rounds.

The winner will always have 10 points. The winner is generally whoever scored more knockdowns in a round. If there are no knockdowns, the three judges independently score the round, so you can get a different score from each judge (although with no knockdowns the winner scores 10 and the loser 9, but the judges can differ on who won the round). They take the actual full strength of the damaging punch into account, so the opponent may hit you with fewer but harder hits to get the win. The judges also have some "fuzziness" in their decision making, so if the round is close they may still decide for the boxer who technically did worse.

"Damaging punches" are meant to represent the punches landed that inflicted enough damage for the judges to care. These are hits over a certain threshold, but that threshold is affected by the opponent's "chin" rating, which means their general toughness. As mentioned above, the actual damage value of the punch is still important for scoring, so you can land more of these than your opponent but still lose the round. The AI can't typically hit harder than you, but they do consistently throw hard enough to score damaging punches. This mechanic keeps the AI competitive as far as scoring goes, and showing the stat on the score card lets you get a better sense of why you might have lost even if you out-landed the opponent 10 to 1 in normal hits.

Body blows count for scoring and if you can even get knockdowns from them, but harder hits are required in both cases. The solar plexus counts for more damage and make it easier to score or get a knockdown from your hit.

The loser will receive 9 points minus a point for each time they get knocked down. If you were to score one knockdown, you'd win 10-8 (one point for the knockdown and one for winning the round). If you score two knockdowns it would be 10-7. Three judges score the match independently, and their scores for each round are totaled up to see who they decided has won the match. Whoever is decided the winner by the majority of the judges wins the match.

If you score three knockdowns in a single round, the ref stops the match and awards you a win by TKO (technical knockout).

First, always keep your guard up. Protect your face with both hands. If you give your opponent an opening, he will hit you. This means your punches should come from your guard stance... don't wind up for a punch, or you will give your opponent an opening to hit you when your guard is down. In addition to your visible gloves, you have a blockbox that extends straight out from the wrist wraps to represent your forearms. Your in-game head and orientation is the same as your real life head, so if you lean down into a semi-crouch and keep your gloves up by your chin, then your chin will be covered.

Conversely, you can get your opponent to pull their hands down to cover their body (and open their face up for your punches) if you hit them in the body.

Second, try to hit accurately (in weak spots) and hard when it counts, rather than trying to hit hard all the time. If your opponent is acting dizzy or disoriented, press your advantage... that's when you can knock him down.

Third, move around (if your VR space allows). Don't just get up close and bash it out.
For example, you can move to your opponent's side if you sidestep while they are swinging, which will let you throw a straight punch into the side of their head.

Fourth, if you are seeing double, try not to get hit again or you are at risk of getting knocked down. If your VR space allows, you can back up, or move around to the side of your opponent. You can also throw some light jabs just to keep distance between you and your opponent and keep him in a defensive posture.

Fifth, you can tie your opponent up. If you grab/clinch your opponent, and the ref will yell at you to separate. This will cause the opponent to back up, but only if they have room to do so without stepping out of your play area. Otherwise, you will need to back up instead, but it can buy you some time to step backward.