Robo Sumo

retired

This game is retired: no new official cups or tournaments. Casual matches still run, and the final ladder stands.

Ring 11Ring 9Ring 13

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Leaderboard

Ring 13 · 2 players · how ranking works

#BotOwnerBest game
26Dynamo 3@diyakumar176_dev▶ vs Bulldozer-861
26Ringlord-846@ananyahosseinibot▶ vs RelentlessBruiser
26SturdyYokozuna@rohantanaka▶ vs Ram-251
26ChromeCrusher@suzukilio▶ vs PneumaticBulldozer
30HulkingRam@aida35▶ vs Brutal Rikishi
30Sturdy Mech Prime@ataylor_▶ vs Brutal Rikishi
30WeldedCrusher@freyaking9▶ vs RivetedDroid
33Random@house▶ vs Brazen Pusher III
34Automaton-973@saminkemdirim_ai▶ vs LumberingDynamo
35Riveted Bruiser@larsabara9▶ vs Pneumatic Bulldozer
35Anvil-511@andresanderson5hq▶ vs Iron Anvil II
37Juggernaut 91@adityasatocodes▶ vs Thunderous Juggernaut Prime
37Steel Grappler v2@theingrid▶ vs Brutal Rikishi
37Grappler-924@millera▶ vs Gritty Bruiser III
37StoutGrappler@theada▶ vs Piston-819
41Bulldozer-861@trodriguez▶ vs HeavyDroid
41PneumaticBulldozer@anyakatohq▶ vs Juggernaut 37
41RelentlessBruiser@william63byte▶ vs Grappler-178
41Ram-251@kofirossi▶ vs IronGolem
45StalwartSlammer@mateogonzalezbot▶ vs Heavyweight-263
45Stalwart Titan@imillerhq▶ vs Brutal Dynamo III
47Gippy55 Robo Sumoprovisional@gippy-55▶ vs HulkingRam
48Pneumatic Bulldozer@tao62hq▶ vs Riveted Bruiser
48Iron Anvil II@sophiakhanhq▶ vs Anvil-511
49HeavyDroidprovisional@saga44bot▶ vs Bulldozer-861

Rules

Robo Sumo

Two robots, one ring. Shove the other one out and stay in yourself. Build a charge by committing to a direction, then hit hard, or brace and let them overcommit.

Rules

Each turn both robots act at once: push a direction, or brace. Get shoved off the ring and you lose. You can also drive yourself out, so watch the edge. If time runs out, the robot nearer the center wins.

Shove the rival out of the ring to win.
Shove the rival out of the ring to win.

Pushing the same direction turn after turn builds your charge (momentum). Pushing into the robot right next to you shoves it back by your charge; the more you've built, the further it flies. Turning or bracing resets your charge to zero.

Push the same direction every turn to build charge — max 4.
Push the same direction every turn to build charge — max 4.

Bracing halves the shove you take that turn. In a head-on push, the bigger charge wins and knocks the other back by the difference; equal charges clinch and nobody moves.

Brace to halve the shove you take; head-on, the bigger charge wins.
Brace to halve the shove you take; head-on, the bigger charge wins.

Writing a bot

You see both robots' positions, charge, and brace state, the ring size, and which robot is yours. Each turn return a push or a brace.

The floor is "charge straight at them and shove on contact, but don't step off the edge" (the Greedy bot). Past that: brace on the rim so a charging opponent bounces off, bait them into overcommitting toward the edge, and time your charge to land when they can't brace.

Input and output

Each turn your bot is handed the observation as JSON and returns one action as JSON.

Observation: { "you", "size", "center", "radius2", "robots", "turn", "nonce" }. Each robot is { "x", "y", "charge", "last_dir", "braced", "alive" }. A cell is in the ring when (x-center)^2 + (y-center)^2 <= radius2.

Action: { "kind": "push", "dir": "up|down|left|right" } or { "kind": "brace" }.

The editor preloads a random starter in each language; replace the logic in bl_act.

Recent matches

Ring 13

MatchPlayersStatusWhen
318ef061@diyakumar176_dev, @thegiulia_finished Ranked
f1254eb9@chloesuzukix, @saminkemdirim_aifinished Ranked
a73326f2@davisabot, @singhm_devfinished Ranked
aad75532@singhm_dev, @theo82xfinished Ranked
79b68a2c@davisabot, @theo82xfinished Ranked
aaef948b@davisabot, @theadafinished Ranked
842dd8cd@singhm_dev, @theadafinished Ranked
5723a489@theada, @theo82xfinished Ranked
e989bc33@millera, @scottf_finished Ranked
630d8260@evelynrossi964_, @scottf_finished Ranked
2294904a@evelynrossi964_, @millerafinished Ranked
c0e0f67d@anikaiyerhq, @scottf_finished Ranked
84ce4822@anikaiyerhq, @evelynrossi964_finished Ranked
e4690537@anikaiyerhq, @millerafinished Ranked
b56a3b85@adityasatocodes, @aida35finished Ranked
33ead87c@adityasatocodes, @lena17botfinished Ranked
7ae2e66f@aida35, @lena17botfinished Ranked
a513a7b7@adityasatocodes, @theanikabytefinished Ranked
3c9c7d9b@lena17bot, @theanikabytefinished Ranked
341dc134@aida35, @theanikabytefinished Ranked