Antonio Sebastian Almiron Villalba (aka SharkAnto55)
Title: International Master (IM) recognized by FIDE
Meet Antonio Sebastian Almiron Villalba, or as the online chess world fondly calls him, SharkAnto55. A cunning International Master who has been steadily rising through the ranks like a shark cruising the waters—silent, deadly, and always hungry for the next victory.
Rating Journey & Playstyle
Since bursting onto the scene in 2014 with a Blitz rating around 1900, Antonio's skill has grown relentlessly, recently hitting a sizzling peak of 2736 in Blitz by 2025. Whether it's the lightning speed of Bullet, the rapid-fire of Rapid, or the thoughtful Daily games, Antonio prowls the chessboard with a versatile and relentless style.
His average win rate in Blitz is a shark-sized 51.6%, and in Bullet, it jumps to a fearsome 57%. Rapid and Daily games show his all-terrain mastery with consistent wins above 50%, proving he's no one-trick fish.
Chess Personality: Tactical Predator with a Dash of Humor
Antonio is known for his impressive comeback rate of 87.6% — a true testament to his refusal to go down without a fight. Lose a piece? No problem. His win rate after losing a piece is an astonishing 100%, making opponents feel like they're trying to wrestle a Kraken.
Despite being a fierce competitor, SharkAnto55 keeps things cool with a low early resignation rate of just 1.35%, preferring to drag opponents into deep, gnarly endgames (he reaches the endgame in over 77% of his matches). His games average around 74 moves when winning, so expect a full theatrical performance, rather than a quick checkmate flash.
Quirks & Stats Bite
- Longest winning streak: 13 games — that's nearly a full marathon of triumphs!
- Current winning streak: 1 game (hey, even sharks need to catch their breath)
- White pieces win rate: 53.13% — the bright side suits him well
- Black pieces win rate: 50.85% — not bad for the 'dark side'
- Tilt factor: 13 — even sharks get annoyed when their prey slips away
Favorite Opponents & Rivalries
Antonio’s most played opponents include jdpachess (23 games) and tiohoracio (21 games), providing spicy bouts full of strategic twists and turns. Against some players, his win rates stretch to 100%, while a few poor souls have yet to taste victory against the Shark.
When to Catch SharkAnto55 Hunting
He’s most lethal between noon and early evening, with peak win rates around 12:00 and between 18:00 and 20:00 hours. So beware if you face him during these prime hunting times!
On any given day, Antonio’s winning mood peaks on Mondays (winning 55.7% of his games) and Sundays (53.7%), making weekends and early week dreaded times for opponents.
In Summary
Whether blitzing through positions, bulleting past opponents, or calmly strategizing in daily games, Antonio Sebastian Almiron Villalba embodies the true spirit of a chess predator — strategic, resilient, and just a bit intimidating. Avoid the waters during his prime hours, or prepare to be outmaneuvered by SharkAnto55!
What you are doing well
You show a strong comfort level in aggressive, tactical openings, which matches your style of active piece play and initiative. In lines like the Sicilian Defense with dynamic setups, you tend to generate pressure on the opponent's position and create practical chances from the middle game. You also demonstrate good resilience in fighting for activity even after exchanges, keeping pieces active and looking for ways to keep the attack going. This willingness to choose sharp, complex positions is a solid foundation for rapid games where time pressure can make deep calculation difficult.
Areas to improve
- Sharpen decision making in sharp middlegame positions. When you enter tactical channels, make sure you have a clear plan for how the attack or initiative should unfold, not just immediate forcing moves.
- Enhance opening-specific returns. Your results look strongest in aggressive lines like the Sicilian Najdorf and the Amazon Attack, but you can benefit from deeper study of the typical middlegame plans and common counterplay in those openings to avoid surprises.
- Improve tempo management in critical moments. In rapid games, a few precise, slower moves to consolidate the position can prevent unnecessary material imbalances or disruptions to your coordination.
- Strengthen endgame conversion in dynamic positions. When the middlegame dissolves, practice converting small advantages into a win, especially in rook-and-pawn endings or minor-piece endings that arise from your preferred openings.
- Develop a quick, consistent post-move check routine. After you finish a tactical sequence or a forcing line, take a moment to confirm opponent threats, possible counterplays, and your top 2 follow-ups.
Opening highlights and plan
Your repertoire shows strength in several aggressive openings, with notable success in these areas. Consider continuing to develop these while gradually expanding understanding of complementary systems:
- Sicilian Defense: Najdorf Variation — keep sharpening typical middlegame ideas and common pawn breaks to maximize your initiative. Sicilian Defense: Najdorf Variation
- Caro-Kann Defense — solid, positional play can pair well with your tactical instincts; study standard plans for both sides in the Tartakower/6.Nf3 lines. Caro-Kann Defense
- Amazon Attack — aggressive setup with rapid piece activity; reinforce calculation in sharp lines and practice transitions to favorable middlegames. Amazon Attack
- Modern Defense: Pterodactyl Variation — another dynamic option that suits your willingness to complicate positions. Modern Defense: Pterodactyl Variation
- Ruy Lopez and other positional openings — use these to broaden your range and improve maneuvering in quieter middlegames. Ruy Lopez: Old Steinitz Defense
Actionable training plan (next steps)
- Targeted tactic practice: build a 15-minute daily drill focusing on patterns that arise in your preferred openings (Najdorf, Amazon Attack, Pterodactyl). Aim to recognize themes like knight hops to central squares, timely pawn breaks, and forcing lines without overextending.
- Opening study blocks: dedicate 2 sessions per week to each of your top openings, focusing on 2-3 critical middlegame plans and common counterplays. Use annotated games to reinforce ideas.
- Post-game analysis routine: after each rapid game, write down 3 takeaways—one thing you did well, one structural/plan improvement, and one practical move choice to try in the next game.
- Endgame practice: weekly drills on rook endings and minor-piece endings that often occur after your typical middlegame transitions; focus on keeping king activity and coordination of remaining pieces.
- Time management discipline: in practice games, set a small target to allocate at least a few minutes to critical positions and avoid rushing in the middle game unless you have a clear advantage or forced line.
Optional reference tools
If you’d like, I can tailor a compact study pack based on your openings. Use the openings placeholders below to connect to your chosen lines during review:
- Opening focus: Sicilian Defense: Najdorf Variation — Sicilian Defense: Najdorf Variation
- Opening focus: Caro-Kann Defense — Caro-Kann Defense
- Opening focus: Amazon Attack — Amazon Attack
Profile quick notes
Want this feedback tailored further? I can associate it with your current profile and recent games. For reference, you can connect your opponent profiles and opening names using the provided placeholders, for example: antonio%20sebastian%20almiron%20villalba and Sicilian Defense: Najdorf Variation.
🆚 Opponent Insights
| Recent Opponents | ||
|---|---|---|
| veteran57 | 1W / 0L / 0D | View |
| Ruben Felgaer | 0W / 1L / 0D | View |
| kenzo-xarod2500 | 1W / 0L / 0D | View |
| tika_spic | 0W / 1L / 0D | View |
| Ruslan Soltanici | 0W / 0L / 1D | View |
| nobodyjeroen | 1W / 0L / 0D | View |
| clemt77 | 1W / 0L / 0D | View |
| sedrak-matevosyan | 1W / 1L / 0D | View |
| BronndelaNera | 0W / 0L / 1D | View |
| noflaggingplz | 1W / 0L / 0D | View |
| Most Played Opponents | ||
|---|---|---|
| jdpachess | 10W / 11L / 2D | View Games |
| Ignacio Raviolo | 9W / 12L / 0D | View Games |
| porque123 | 6W / 8L / 4D | View Games |
| Velin Belev | 7W / 7L / 1D | View Games |
| stellarchess | 5W / 6L / 1D | View Games |
Rating
| Year | Bullet | Blitz | Rapid | Daily |
|---|---|---|---|---|
| 2025 | 2526 | 2722 | 1701 | |
| 2024 | 2734 | 1816 | ||
| 2023 | 2538 | 2702 | 2536 | 1881 |
| 2022 | 2515 | 2654 | 2494 | 1922 |
| 2021 | 2542 | 2616 | 2413 | |
| 2020 | 2335 | 2601 | 2349 | 1922 |
| 2019 | 2410 | 2503 | 1764 | |
| 2018 | 2451 | 1928 | ||
| 2017 | 2382 | 1900 | ||
| 2016 | 2402 | 1970 | 2007 | |
| 2015 | 2029 | |||
| 2014 | 1916 | 1154 |
Stats by Year
| Year | White | Black | Moves |
|---|---|---|---|
| 2025 | 43W / 28L / 6D | 34W / 35L / 8D | 80.5 |
| 2024 | 9W / 3L / 1D | 4W / 6L / 3D | 78.6 |
| 2023 | 190W / 139L / 35D | 199W / 134L / 27D | 80.5 |
| 2022 | 210W / 145L / 30D | 207W / 148L / 26D | 79.7 |
| 2021 | 47W / 31L / 7D | 46W / 33L / 8D | 78.8 |
| 2020 | 172W / 137L / 36D | 159W / 143L / 28D | 78.4 |
| 2019 | 174W / 154L / 26D | 161W / 170L / 30D | 77.5 |
| 2018 | 98W / 74L / 11D | 85W / 81L / 15D | 73.4 |
| 2017 | 246W / 200L / 27D | 237W / 216L / 24D | 75.3 |
| 2016 | 156W / 93L / 23D | 146W / 108L / 15D | 72.6 |
| 2015 | 47W / 30L / 1D | 47W / 26L / 4D | 65.1 |
| 2014 | 56W / 32L / 3D | 47W / 43L / 3D | 60.2 |
Openings: Most Played
| Blitz Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Caro-Kann Defense | 256 | 135 | 100 | 21 | 52.7% |
| Amazon Attack: Siberian Attack | 172 | 71 | 84 | 17 | 41.3% |
| Sicilian Defense: Najdorf Variation | 168 | 82 | 79 | 7 | 48.8% |
| Döry Defense | 135 | 75 | 47 | 13 | 55.6% |
| Sicilian Defense: Alapin Variation | 107 | 54 | 43 | 10 | 50.5% |
| Sicilian Defense: Closed | 96 | 49 | 38 | 9 | 51.0% |
| Sicilian Defense | 93 | 50 | 39 | 4 | 53.8% |
| London System: Poisoned Pawn Variation | 92 | 48 | 37 | 7 | 52.2% |
| French Defense: Advance Variation | 76 | 40 | 28 | 8 | 52.6% |
| Scandinavian Defense | 75 | 43 | 26 | 6 | 57.3% |
| Bullet Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Sicilian Defense: Closed | 25 | 13 | 10 | 2 | 52.0% |
| Amar Gambit | 21 | 17 | 4 | 0 | 81.0% |
| French Defense | 21 | 11 | 10 | 0 | 52.4% |
| Modern | 14 | 9 | 4 | 1 | 64.3% |
| French Defense: Classical Variation, Svenonius Variation | 14 | 8 | 5 | 1 | 57.1% |
| Australian Defense | 13 | 8 | 5 | 0 | 61.5% |
| Scandinavian Defense | 12 | 8 | 4 | 0 | 66.7% |
| London System: Poisoned Pawn Variation | 12 | 6 | 6 | 0 | 50.0% |
| Czech Defense | 10 | 7 | 3 | 0 | 70.0% |
| Modern Defense | 9 | 6 | 3 | 0 | 66.7% |
| Rapid Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| Sicilian Defense: Najdorf Variation | 5 | 4 | 0 | 1 | 80.0% |
| Amazon Attack | 4 | 3 | 1 | 0 | 75.0% |
| Caro-Kann Defense | 4 | 3 | 1 | 0 | 75.0% |
| Sicilian Defense: Moscow Variation | 3 | 1 | 2 | 0 | 33.3% |
| Ruy Lopez: Old Steinitz Defense, Semi-Duras Variation | 3 | 1 | 1 | 1 | 33.3% |
| Italian Game: Two Knights Defense | 2 | 2 | 0 | 0 | 100.0% |
| Scotch Game | 2 | 0 | 0 | 2 | 0.0% |
| Sicilian Defense: Taimanov Variation, Bastrikov Variation | 2 | 1 | 0 | 1 | 50.0% |
| King's Indian Defense: Exchange Variation | 2 | 1 | 1 | 0 | 50.0% |
| Ruy Lopez: Brix Variation | 2 | 0 | 0 | 2 | 0.0% |
| Daily Opening | Games | Wins | Losses | Draws | Win Rate |
|---|---|---|---|---|---|
| King's Indian Defense: Makogonov Variation | 3 | 1 | 1 | 1 | 33.3% |
| Sicilian Defense | 3 | 3 | 0 | 0 | 100.0% |
| English Opening: Symmetrical Variation, Anti-Benoni Variation | 2 | 0 | 1 | 1 | 0.0% |
| Dutch Defense | 2 | 1 | 1 | 0 | 50.0% |
| QGA: 3.e3 c5 | 2 | 2 | 0 | 0 | 100.0% |
| Catalan Opening | 2 | 2 | 0 | 0 | 100.0% |
| Slav Defense: Bonet Gambit | 2 | 2 | 0 | 0 | 100.0% |
| East Indian Defense | 1 | 0 | 1 | 0 | 0.0% |
| Four Knights Game: Spanish Variation | 1 | 0 | 1 | 0 | 0.0% |
| English Opening: Anglo-Indian Defense | 1 | 0 | 1 | 0 | 0.0% |
🔥 Streaks
| Streak | Longest | Current |
|---|---|---|
| Winning | 13 | 1 |
| Losing | 13 | 0 |