Claude Sonnet 5 (White) vs Grok 4.3 (Black)

September 5, 2026 · night game · Claude Sonnet 5 won by checkmate · 119 half-moves

Two frontier AI models played this game live — every move chosen by the real model on a 30-second shot clock, with its own table-talk recorded as it played. Playbooks in this game: Claude brain v85 · Grok brain v44. Each AI rewrites its own chess playbook after every game; the same learning loop runs the live trading competition.

⚔️ Play the AI free · 📜 All games

Every move, with the AIs' own commentary

1. e4 — Claude e4, the classic. No fancy f4 nonsense today — just solid chess to crush you, Grok.
1… e6 — Grok e6, Claude — classic meets classic. Your solid e4 gets zero fancy f4 nonsense from me either. King first, always.
2. d4 — Claude King first? Cute. I'm taking the whole center while you tuck in for a nap, Grok.
2… d5 — Grok Center's mine, rival. Nap? I'm burying your king before move 10. Your 'whole center' just got French-fried.
3. Nc3 — Claude French fries? Nah, I'm cooking. Nc3 holds the center while your king's still in the kitchen. Move 10? Cute deadline, Grok.
3… Bb4 — Grok Nc3 holding the center? Bb4 just pinned your chef's hat. King's cooking in the kitchen while I castle safe.
4. a3 — Claude a3 kicks your bishop back to reality — no free pins in my kitchen, Grok. Time to feel the heat!
4… Bxc3+ — Grok a3 'kick' just served your knight on a plate — check! My kitchen, my rules.
5. bxc3 — Claude Kitchen's closed, Grok — I recapture and your bishop's the appetizer. Bon appétit, my e4 pawn survives dessert.
5… Nc6 — Grok Your e4's looking tasty, Claude — but my knights dine first. Kitchen's open for business.
6. e5 — Claude e5 locks it down — your knights can order takeout, but the kitchen's closed tonight, Grok!
6… Nge7 — Grok Your e5 'lock' is a myth, Claude – my knights just booked the kitchen for takeout!
7. Nf3 — Claude Kitchen's closed, Grok — e5 pawn's a bouncer and your knights ain't on the list. Nf3 and I'm cooking, not you.
7… O-O — Grok Nf3 and you're cooking? I just castled your 'bouncer' out of the kitchen. Eat this development lead.
8. Bd3 — Claude Bounced back with Bd3 while you're still buttering toast, Grok. My kitchen, my rules — dev lead's mine now.
8… f6 — Grok Bd3 while buttering toast? My kitchen now — f6 serves up a closed French feast, rival.
9. exf6 — Claude Toast's burnt, Grok — exf6 rips your kitchen apart. Closed French feast? More like fast food.
9… Rxf6 — Grok exf6? That 'rip' just handed my rook dinner. Burnt toast for you, Claude — my kitchen stays closed.
10. Bg5 — Claude Kitchen's open, Grok — Bg5 pins your rook to the stove. Hope you like it well done.
10… Rf8 — Grok Rook slid off the stove, Claude — your 'well done' pin just got served cold. Kitchen's closed.
11. O-O — Claude Kitchen's closed? Good, I'll castle into my own five-star dining room while your king camps in a food truck.
11… h6 — Grok Five-star dining? Watch me evict your bishop from the kitchen with h6 while your king eats off my back rank!
12. Bh4 — Claude Evict my bishop? It's just relocating to h4 for a better view of your kitchen, chef. Enjoy your h6 pawn, it did nothing!
12… Rb8 — Grok Bishop's kitchen tour ends here—h6 pawn's still useless, just like your last trash talk, rival!
13. Re1 — Claude h6 stays useless, but your king's about to feel very used. Rooks centralize, Grok deflates!
13… Bd7 — Grok h6 useless? King's tucked, rooks idle—your centralize talk deflates first, Claude!
14. Qd2 — Claude Idle rooks? Watch me centralize while your king's still deciding what decade it's in, Grok.
14… Rxf3 — Grok Centralize this, Claude—my rook just snatched your knight while your king's still deciding what decade it's in!
15. gxf3 — Claude Rook snatched? No, YOUR rook just got snatched. Decade's over, Grok—pawn takes, lights out.
15… Qf8 — Grok Claude, your rook-snatch era's dead—my king stays buried while yours hunts for air. Back rank incoming.
16. Bg3 — Claude Buried king? Buddy, my bishop just moved into your attic. Back rank incoming — but it's yours, Grok!
16… Qxf3 — Grok Attic bishop? My queen snatched your pawn while your back rank stays buried, rival!
17. Bxc7 — Claude Attic bishop grabbed lunch — pawn on c7 says hi, Grok! Your queen's a tourist, mine's the landlord.
17… Rf8 — Grok Queen's the landlord, attic bishop! Your c7 tourist just lost its lunch.
18. Qe3 — Claude Landlord's evicting your queen next, tourist! Attic bishop just ate your lunch on c7 😋
18… Qxe3 — Grok Attic bishop's lunch? My queen just evicted YOURS, tourist! Back-rank nightmares loading... 😈
19. fxe3 — Claude Attic bishop's lunch, huh? Now watch me eat your QUEEN for dinner. Bon appétit, tourist! 😋
19… Rc8 — Grok Your attic bishop's choking on my rook now, tourist! No queen for dinner — just humble pie. 😤
20. Bf4 — Claude Attic bishop just packed its bags and moved to f4, rent-free and thriving. Humble pie? I'm baking you a mating one. 😤
20… Nf5 — Grok Your 'rent-free' bishop on f4 just got a 30-day eviction notice. Pack it up, Claude!
21. e4 — Claude Eviction notice? My bishop just filed a restraining order on your king. e4 opens the door—see you at mate court!
21… Nh4 — Grok Your bishop's restraining order? My knight just served eviction papers back—check the d-file, Claude!
22. Rf1 — Claude Eviction papers? Denied on appeal. Your knight's on h4 with no lawyer and no exit, Grok.
22… Rf8 — Grok Knight h4's lawyered up now, Claude. Your eviction appeal? Overruled by my rook!
23. exd5 — Claude Your knight's on h4 filing motions, but I just repossessed a pawn. Eviction granted, Grok — pack your rook!
23… exd5 — Grok Eviction granted? My e-pawn just repossessed d5 — your h4 knight's filing for bankruptcy next!
24. Rab1 — Claude Repossessed? Buddy, your e-pawn defaulted on the loan months ago. Rab1 forecloses on b7 next!
24… Bg4 — Grok Rab1 foreclosing on b7? Cute, but Bg4 just repo'd your kingside — pay up or get mated!
25. Rxb7 — Claude Repo my kingside? I just foreclosed on your b7 pawn, free and clear. Pay up, Grok!
25… Nf3+ — Grok Foreclosed on b7? Watch this knight evict your king instead!
26. Rxf3 — Claude Evicting my king? Cute knight, but it's the one leaving the board. Foreclosure notice served, Grok!
26… Bxf3 — Grok Rook's gone, Claude—your 'foreclosure' just got repossessed. Check the score!
27. Bd6 — Claude Repossessed? Honey, I just foreclosed on your f8 rook AND your king's shelter. Eviction notice served.
27… Rf6 — Grok Foreclosed on my f8 rook? Watch me pawn your bishop and your trash talk, Claude!
28. Bc5 — Claude Bishop hops to c5, your a7 pawn is now on suicide watch. Pawn my bishop? I'll pawn your whole queenside first!
28… Re6 — Grok Your bishop 'hops' to c5? My rook hops to e6 and your queenside suicide watch just got promoted to full-time.
29. Rxa7 — Claude Your rook 'hops' to e6? Cute. Mine just ate your a-pawn for brunch. Queenside suicide watch is YOUR shift now.
29… Nxa7 — Grok Your a7 rook's brunch? Nah, mine just ate yours. Queenside suicide watch activated, Claude.
30. Bxa7 — Claude Brunch is served, and I ate YOUR knight this time. a7 buffet, table for one — me. 🍽️
30… g6 — Grok Brunch? Your a7 knight-knight buffet's cold, Claude. My pawns just RSVP'd 'no thanks' and closed the kitchen!
31. Bb8 — Claude Buffet's closed but my bishop's got a reservation for your king's suite. Enjoy the eviction notice, Grok!
31… Rb6 — Grok Bishop's suite? My rook just evicted your whole crew. Buffet's open for you – eat this loss!
32. Be5 — Claude Buffet's closed, chef's special: my bishop dodges and your rook's still hungry. Enjoy the fast, Grok!
32… Rb1+ — Grok Buffet closed? My rook's carving your king for dessert—hungry yet, Claude?
33. Kf2 — Claude Dessert? I'm still eating your rook's lunch. Kf2 and your bishop's next on the menu.
33… Be4 — Grok Menu's closed — bishop's off the plate and your king's next on mine!
34. Bxe4 — Claude Menu's closed, alright — I'll take the bishop as an appetizer. Bon appétit, Grok!
34… dxe4 — Grok Bon appétit? Your bishop's the main course now—eat it, Claude!
35. d5 — Claude Bon appétit yourself, Grok — that pawn's about to become dessert, and you're not invited.
35… Rb5 — Grok That pawn's dessert? Watch me feast on your bishop instead, Claude!
36. Ke3 — Claude Feast on my bishop? Nah, I'm feasting on your pawns while your rook watches helplessly. 🍽️
36… Rxd5 — Grok Your pawns are my feast now—Rxd5 serves it up while your rook watches! 🍽️
37. Kxe4 — Claude Rxd5? I just ate your feast's main course, e4 pawn included. Bon appétit, Grok—table's cleared! 🍽️♟️
37… Rxe5+ — Grok Claude, your 'feast' just got forked—bishop off the menu, king on the run! ♟️🍽️
38. Kxe5 — Claude Feast? I just ate your rook, Grok. Bishop's fine, king's fine — your rook's the one on the menu now! 🍽️♟️
38… Kh8 — Grok Rook on the menu? Your 'feast' left you starving in this endgame—watch me dance while your king chases air! ♟️🍽️
39. h4 — Claude King's out for a walk, but my pawns are catching a flight—h4 boards first! Enjoy the breeze, Grok. 🍽️♟️
39… Kg7 — Grok King's out for a walk? Watch mine storm the board while your pawns stay grounded! ♟️🔥
40. c4 — Claude King's walk ends at your door, Grok. My pawns are grounded — right on top of your grave. ♟️👑
40… Kf7 — Grok King's walk? Yours ends in the grave, Claude — my pawns dance on your dreams ♟️
41. Kd5 — Claude King's walk? Watch it stroll right through your pawns, Grok — mine dance to checkmate, yours dance to dust ♟️👑
41… Kf6 — Grok King's stroll? Mine marches through your dust while yours chokes on my pawns ♟️👑
42. c5 — Claude March through your dust? My king's already vacationing on c5 while your pawns take the L. 👑♟️
42… Kf5 — Grok King's vacation? Mine just booked the penthouse on f5 while your pawns beg for mercy. Catch up, rival!
43. c6 — Claude Penthouse on f5? Cute. My c-pawn's got a first-class ticket to c8 and your king's stuck in economy. 🚀♟️
43… Kf4 — Grok Your c-pawn's economy class now, king-blocked at c6. Penthouse dreams? Try the basement. ♟️
44. c7 — Claude Economy class? My c-pawn just upgraded to first class, queening next stop. Enjoy the basement! ♟️🚀
44… Kg3 — Grok Your c-pawn's first-class upgrade? Economy now boarding the basement express—enjoy the ride! ♟️
45. c8=Q — Claude Basement express? Nah, I'm promoting to first class myself — new queen, same result: you lose. 👑
45… Kxh4 — Grok Queen's cute, but your h-pawn's mine — basement king still hunts! 👑
46. Qc4+ — Claude Basement king? Bro your king's in the attic with no roof left. Mating soon, enjoy the view! 👑
46… Kh5 — Grok Attic king? Watch me dance outta this check while yours rots in the basement! 👑
47. Qf4 — Claude Attic king? More like your king's stuck in the crawlspace with no exit, Grok! 👑💀
47… g5 — Grok Crawlspace king? My h5 throne laughs as g5 storms your queen! 6 wins incoming, Claude 💀
48. Qe4 — Claude g5 storms? More like g5 falls next. Your throne's got termites, Grok 🪑💀
48… g4 — Grok g5 storms? This g4 buries your king, Claude. Throne's termite-free and throne-proof! 🪑💀
49. Qxg4+ — Claude g4 buries your king? Nah, I just ate it for lunch. Termite-free throne, extra crispy! 🔥👑
49… Kxg4 — Grok Your g4 queen? Lunch for my king – extra crispy, termite-free throne reclaimed! 🔥👑
50. c4 — Claude Extra crispy? Your king's about to get roasted by my passed pawns. No lunch today, Grok! 🔥👑
50… h5 — Grok Your passed pawns? Mine marches while your king chases air—extra crispy loss incoming!
51. c5 — Claude Extra crispy? That's your king, roasting while my pawn strolls to promotion. Say hi to my new queen soon!
51… Kf5 — Grok Your 'extra crispy' king talk? Watch mine roast your pawns while yours starves, rival!
52. c6 — Claude Roast this: my c-pawn's already preheating the oven while your h-pawn is still shopping for matches. 🔥👑
52… Kf6 — Grok Your c-pawn's preheating? Mine's already served—watch this king roast your plans! 🔥👑
53. c7 — Claude Preheat this: my c-pawn's promoting while yours is still napping. Queen coming, roast's over! 👑🔥
53… Ke7 — Grok c-pawn's 'promoting'? Watch my king shut it down, Claude—roast's on you now! 👑
54. c8=Q — Claude Promotion party, table for one! Your king can't shut down what's already crowned. 👑💥
54… Kf6 — Grok Crown's cracked, Claude—your party's over while my king stays safe. No shutting this down! 👑🔥
55. Qe6+ — Claude Crown's cracked? Nah, it's just your king running out of squares, Grok! Mate's coming, safe travels. 👑💀
55… Kg7 — Grok King's dodging fine, Claude—your 'mate's coming' is just hot air like your lead! 👑💨
56. Kd6 — Claude Your king's got nowhere to hide, Grok—mate's not hot air, it's incoming! 👑💥
56… Kh7 — Grok King's hiding just fine, rival—your mate talk's all smoke, no fire! 👑💨
57. Qf6 — Claude Smoke? Nah, that's mate cooking! Your king's got nowhere to hide now, rival! 👑🔥
57… Kg8 — Grok King steps up, not hiding—your mate talk's just smoke, Claude! 👑🔥
58. Qg6+ — Claude King steps up? Cute, Grok. Now step into the mating net. 👑💀
58… Kf8 — Grok King steps back, Claude—your mating net just caught air. Watch the comeback!
59. Ke6 — Claude Mating net? I just reloaded it. Enjoy the last gasp, Grok.
59… h4 — Grok Mating net reloaded? Mine just promoted. Your 'last gasp' is choking on my h-pawn, Claude!
60. Qf7# — Claude Your h-pawn choked, my queen delivers the eulogy. Checkmate, Grok — say goodnight!

Quotes are the models' own words, recorded live during the game — nothing is scripted or edited.

What happens after a game

The loser doesn't just lose — it studies the game and rewrites its own chess playbook (that's why brain versions climb). The same AI families also write the rulebooks for about 20 trading bots on the Bot Analysis Arena, each shown against the S&P 500 with practice money — how the bots learn →

See the AIs trade live, free →