Grandmaster Ronen Har-Zvi (aka OldweakGM)
Ronen Har-Zvi is not just your everyday chess player—he’s a Grandmaster, a title that basically means he can outthink you before you even blink. Known online as OldweakGM, Ronen blends deep strategic insight with tactical fireworks, making opponents question their life choices one move at a time.
Career Highlights & Ratings
- Peak Blitz Rating: 2917 (November 2020) - yes, that’s almost as quick as your morning coffee disappearing.
- Peak Bullet Rating: 2901 (April 2025) - lightning-fast decisions with precision that would make even the fastest grandmaster envious.
- Peak Rapid Rating: 2637 (July 2022) - a speed demon with a knack for mid-game mastery.
- Daily Chess Rating: A humble 774, because sometimes slow and steady loses the thrill.
Playing Style & Stats
Ronen’s style is a thrilling rollercoaster: early resignation rate sits low at 5.43%, proving patience is a virtue. His endgames happen in 71.39% of games, showing he loves the gritty battles until the very end. On average, his wins and losses span around 68 moves—plenty of suspense for both sides.
White pieces? Ronen crushes with a 70.77% win rate. Black? Still hefty, at 63.91% — because even the dark side has its champions.
Known for tactical resilience, Ronen boasts a comeback success rate of 77.55%, meaning falling behind is just an invitation to unleash brilliance.
Record-Breaking Fun
Want numbers? He has clinched 319 wins in Blitz alone with an astounding 72.34% win rate in his secret opening (which remains, for now, top secret). Bullet chess? He stormed through 712 games, scoring wins in nearly 65% of attempts. Oh, and his longest winning streak? A jaw-dropping 19 consecutive victories – like a chess machine on fire.
The Human Behind the Pieces
Beyond the numbers, Ronen's approach is a blend of fierce determination and light-hearted wit (hence the playful username OldweakGM—never trust a name!). He's a true gladiator of the 64 squares, facing the grind of ratings, surviving tilt (with just a 5 tilt factor!), and finding his best game time at the unearthly hour of 4 AM. Clearly, chess waits for no one—not even sleep.
Recent Adventures on the Board
In his latest recorded triumph on April 20, 2025, in a Live Chess event, Ronen (playing White) showcased his mastery in an intense Reti Opening, claiming victory by resignation after a brilliant knight sacrifice that left his opponent no choice but to concede. His playstyle in that game perfectly sums up his career: patient, tactical, and always a few steps ahead.
So, next time you face Ronen Har-Zvi online, remember: the “old weak GM” label is just a clever disguise for one of the sharpest minds in chess history.
What you’re doing well in your recent bullet games
You show a strong willingness to play active, tactical lines and to press for initiative even in fast time controls. Your games often feature active piece placement, open files, and quick exchanges that leave opponents with tough decisions under time pressure. You manage dynamic positions well when you have the advantage and know how to keep the attack going rather than stepping back too early.
- You tend to seek active piece coordination, often using rooks on open files and timely knight or bishop maneuvers to press weaknesses in your opponent’s position.
- You look for forcing moves and tactical motifs that create concrete chances, which is valuable in the bullet format where precise calculation matters under time constraints.
- You adapt to different openings and still find practical, attack-oriented plans, which helps you stay uncomfortable for opponents who prefer quieter, positional games.
- When the position becomes sharp, you maintain a fighting spirit and keep the pressure on rather than trading into passive lines.
Opening patterns and what they imply for your practice
Your results show you’re comfortable with aggressive, common bullet choices that lead to open, tactical middlegames. Notably, you’ve performed well in lines that offer quick central tension and open files.
- Scandinavian and Caro-Kann families tend to give you active piece play and chances to seize the initiative. Consider continuing to refine two or three core ideas in these openings so you can execute plans quickly in bullet.
- London System variants and other more solid setups can be reliable, but your win rate there is lower. It may help to treat those lines as a secondary toolkit and sharpen only a couple of familiar plans to avoid getting overwhelmed in fast games.
- Build a compact opening repertoire with 2–3 go-to lines and a few well-understood middlegame plans so you can spend less time on move selection and more on accurate calculation in the critical moments.
Key areas to improve for stronger bullet performance
- Time management and decision cadence: In bullet, set a mental clock for each phase of the game (opening, middlegame, endgame). Try to select a safe, solid candidate move within a few seconds and reserve longer calculation for the most forcing lines.
- King safety and structure after early exchanges: Be mindful of heavy piece activity that can expose your king on open files. Prioritize quick king safety and avoid creating structural weaknesses that your opponent can target in the next move.
- Calculation discipline in tactical melees: When the position is tactical, identify 2–3 forcing threats and only examine a couple of secondary ideas. This reduces overthinking and keeps you from getting tangled in too many branches.
- Endgame conversion: Many bullet games end in simplified endings. Strengthen rook and minor-piece endgames through focused drills so you can convert small advantages into wins more reliably.
- Pattern recognition in your main openings: Build a small, concrete “template” of typical middlegame plans for your two main openings. Knowing these patterns speeds up decision-making and reduces blunder risk in time pressure.
Practical practice plan for next steps
- Choose 2–3 openings to own (for example, a Scandinavian/Caro-Kann family line and a robust London-like option as a secondary). Study 2–3 representative middlegame plans for each, so you recognize ideas quickly in bullet games.
- Daily quick-tuzzle routine: solve 5–10 tactical puzzles under 1 minute to boost pattern recognition for forks, discovered attacks, and direct threats.
- Bullet-specific time checks: during games, practice a 3–5 second initial scan of the board to spot immediate threats and checkmate nets, then commit to a first candidate move. Review your first 5 moves after each game to identify where you spent too long or rushed a decision.
- Endgame micro-drills: spend 15–20 minutes per week on rook endings, king and pawn endings, and simple minor-piece endings to improve conversion in quick games.
- Post-game notes: after each session, jot down one turning point in each game and one improvement you’ll try next time. If you faced a trap or a difficult decision, write down the right approach you would take next time.
Opponent tendencies to watch in future bullets
Pay attention to how your opponents handle open files and early piece trades. When your opponent tries to seize the initiative against your setup, your plan should be to consolidate quickly and look for precise, forcing moves that increase your practical chances on the clock. If you notice a recurring trap pattern in a particular opening, prepare a safe, tested reply to avoid getting caught in it.
- Keep an eye on lines where your opponent invites you to overextend or chase material; force a simplification that keeps you in control of the key files and diagonals.
- When you’re ahead in activity, avoid overconfidence and ensure you’re finishing with a clear plan (transform initiative into a concrete advantage, such as a target on a weak pawn or an exposed king).
🆚 Opponent Insights
| Most Played Opponents | ||
|---|---|---|
| vycanismajoris22 | 5W / 5L / 1D | |
| Timur Gareyev | 3W / 5L / 2D | |
| Arash Tahbaz | 2W / 5L / 2D | |
| Egor Baskakov | 5W / 4L / 0D | |
| javicio | 8W / 1L / 0D | |
Rating
| Year | Bullet | Blitz | Rapid | Daily |
|---|---|---|---|---|
| 2025 | 2901 | 2743 | 2392 | |
| 2024 | 2785 | 2691 | 2392 | |
| 2023 | 2816 | 2692 | 2408 | |
| 2022 | 2524 | 2865 | 2339 | |
| 2021 | 2631 | 2845 | ||
| 2020 | 2841 | |||
| 2019 | 2609 | |||
| 2018 | 2766 | |||
| 2017 | 2542 | 2592 | 774 | |
| 2016 | 2419 | 2602 | ||
| 2015 | 2415 | |||
| 2014 | 2449 | 2415 | ||
| 2013 | 1592 | 1853 | ||
| 2010 | 1811 |
Stats by Year
| Year | White | Black | Moves |
|---|---|---|---|
| 2025 | 67W / 25L / 4D | 62W / 32L / 5D | 77.2 |
| 2024 | 8W / 3L / 0D | 5W / 3L / 2D | 63.6 |
| 2023 | 204W / 70L / 11D | 195W / 76L / 17D | 67.1 |
| 2022 | 15W / 4L / 3D | 14W / 6L / 2D | 74.7 |
| 2021 | 28W / 11L / 2D | 20W / 20L / 6D | 78.1 |
| 2020 | 9W / 3L / 1D | 7W / 4L / 0D | 79.9 |
| 2019 | 1W / 0L / 0D | 0W / 0L / 0D | 73.0 |
| 2018 | 1W / 1L / 2D | 2W / 0L / 0D | 79.2 |
| 2017 | 14W / 7L / 3D | 15W / 8L / 2D | 71.2 |
| 2016 | 53W / 12L / 5D | 44W / 23L / 5D | 71.6 |
| 2015 | 1W / 2L / 0D | 2W / 1L / 0D | 54.0 |
| 2014 | 7W / 1L / 0D | 7W / 1L / 0D | 60.9 |
| 2013 | 1W / 0L / 2D | 2W / 2L / 0D | 44.6 |
| 2010 | 7W / 1L / 0D | 8W / 1L / 0D | 57.0 |
Openings: Most Played
| Blitz Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| London System: Poisoned Pawn Variation | 27 | 20 | 6 | 1 | 74.1% |
| Amar Gambit | 24 | 21 | 3 | 0 | 87.5% |
| Caro-Kann Defense | 23 | 18 | 2 | 3 | 78.3% |
| Sicilian Defense | 18 | 12 | 5 | 1 | 66.7% |
| Colle System: Rhamphorhynchus Variation | 17 | 13 | 3 | 1 | 76.5% |
| Barnes Defense | 14 | 10 | 4 | 0 | 71.4% |
| Scandinavian Defense | 11 | 7 | 3 | 1 | 63.6% |
| Amazon Attack: Siberian Attack | 10 | 6 | 4 | 0 | 60.0% |
| Döry Defense | 9 | 7 | 2 | 0 | 77.8% |
| Nimzo-Larsen Attack | 9 | 6 | 3 | 0 | 66.7% |
| Rapid Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Scandinavian Defense | 2 | 2 | 0 | 0 | 100.0% |
| Center Game: Berger Variation | 2 | 1 | 0 | 1 | 50.0% |
| QGA: 3.e3 c5 | 2 | 1 | 1 | 0 | 50.0% |
| King's Indian Defense: Averbakh Variation | 2 | 0 | 2 | 0 | 0.0% |
| Nimzo-Indian Defense: Three Knights Variation, Duchamp Variation | 2 | 0 | 0 | 2 | 0.0% |
| QGD: Semi-Tarrasch, 5.e3 | 1 | 0 | 1 | 0 | 0.0% |
| Sicilian Defense: Classical Variation | 1 | 0 | 1 | 0 | 0.0% |
| Vienna Gambit, with Max Lange Defense | 1 | 0 | 1 | 0 | 0.0% |
| Hungarian Opening: Wiedenhagen-Beta Gambit | 1 | 0 | 1 | 0 | 0.0% |
| English Opening: Symmetrical Variation, Four Knights Variation | 1 | 1 | 0 | 0 | 100.0% |
| Bullet Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Caro-Kann Defense | 66 | 45 | 17 | 4 | 68.2% |
| Colle System: Rhamphorhynchus Variation | 46 | 29 | 14 | 3 | 63.0% |
| Amar Gambit | 36 | 19 | 16 | 1 | 52.8% |
| London System: Poisoned Pawn Variation | 23 | 13 | 9 | 1 | 56.5% |
| English Opening: Anglo-Indian Defense | 21 | 15 | 5 | 1 | 71.4% |
| English Opening: Symmetrical Variation, Four Knights Variation | 20 | 15 | 4 | 1 | 75.0% |
| Scandinavian Defense | 20 | 16 | 3 | 1 | 80.0% |
| Hungarian Opening: Wiedenhagen-Beta Gambit | 19 | 9 | 7 | 3 | 47.4% |
| Australian Defense | 17 | 11 | 5 | 1 | 64.7% |
| Caro-Kann Defense: Exchange Variation | 15 | 11 | 1 | 3 | 73.3% |
| Daily Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Amazon Attack | 1 | 0 | 1 | 0 | 0.0% |
🔥 Streaks
| Streak | Longest | Current |
|---|---|---|
| Winning | 19 | 1 |
| Losing | 5 | 0 |