diff --git a/minmax-java/README.md b/minmax-java/README.md
new file mode 100644
index 0000000..4810cac
--- /dev/null
+++ b/minmax-java/README.md
@@ -0,0 +1,15 @@
+# Connect Four Template
+
+A start of a project implementing a variant of the game "[Connect Four](https://de.wikipedia.org/wiki/Vier_gewinnt)".
+
+## Mission
+
+1. Extend the existing code such that the GreedyPlayer works.
+2. Implement a strong opponent using MinMax/Negamax with a fixed depth (like 10).
+3. Implement a perfect Player and optimize it for speed.
+
+## Resources
+
+- https://de.wikipedia.org/wiki/Minimax-Algorithmus#Implementierung
+- https://de.wikipedia.org/wiki/Alpha-Beta-Suche#Implementierung
+- https://en.wikipedia.org/wiki/Zobrist_hashing
diff --git a/minmax-java/build.gradle b/minmax-java/build.gradle
new file mode 100644
index 0000000..c062119
--- /dev/null
+++ b/minmax-java/build.gradle
@@ -0,0 +1,26 @@
+plugins {
+	id 'java'
+}
+
+group = 'ch.bbw.m411'
+version = '0.0.1-SNAPSHOT'
+
+java {
+	toolchain {
+		languageVersion = JavaLanguageVersion.of(17)
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	testImplementation 'org.junit.jupiter:junit-jupiter-api:5.9.1'
+	testImplementation 'org.assertj:assertj-core:3.23.1'
+	testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.9.1'
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}
diff --git a/minmax-java/gradle/wrapper/gradle-wrapper.jar b/minmax-java/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..249e583
Binary files /dev/null and b/minmax-java/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/minmax-java/gradle/wrapper/gradle-wrapper.properties b/minmax-java/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..b916c04
--- /dev/null
+++ b/minmax-java/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionSha256Sum=f6b8596b10cce501591e92f229816aa4046424f3b24d771751b06779d58c8ec4
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/minmax-java/gradlew b/minmax-java/gradlew
new file mode 100755
index 0000000..a69d9cb
--- /dev/null
+++ b/minmax-java/gradlew
@@ -0,0 +1,240 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/minmax-java/gradlew.bat b/minmax-java/gradlew.bat
new file mode 100644
index 0000000..f127cfd
--- /dev/null
+++ b/minmax-java/gradlew.bat
@@ -0,0 +1,91 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/minmax-java/settings.gradle b/minmax-java/settings.gradle
new file mode 100644
index 0000000..e69de29
diff --git a/minmax-java/src/main/java/ch/bbw/m411/connect4/Connect4ArenaMain.java b/minmax-java/src/main/java/ch/bbw/m411/connect4/Connect4ArenaMain.java
new file mode 100644
index 0000000..3101d8c
--- /dev/null
+++ b/minmax-java/src/main/java/ch/bbw/m411/connect4/Connect4ArenaMain.java
@@ -0,0 +1,194 @@
+package ch.bbw.m411.connect4;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.Scanner;
+
+/**
+ * Plays a game of Connect Four on a 4x7 board (a variation of the original 6x7 board).
+ * The pieces fall straight down, occupying the lowest available space within the column.
+ */
+public class Connect4ArenaMain {
+
+	static final int WIDTH = 7;
+
+	static final int HEIGHT = 4;
+
+	static final int NOMOVE = -1;
+
+	public static void main(String[] args) {
+		new Connect4ArenaMain().play(new HumanPlayer(), new GreedyPlayer());
+	}
+
+	static String toDebugString(Stone[] board) {
+		var sb = new StringBuilder();
+		for (int r = 0; r < HEIGHT; r++) {
+			for (int c = 0; c < WIDTH; c++) {
+				var value = board[r * WIDTH + c];
+				sb.append(value == null ? "." : (value == Stone.RED ? "X" : "O"));
+			}
+			sb.append("-");
+		}
+		return sb.toString();
+	}
+
+	Connect4Player play(Connect4Player red, Connect4Player blue) {
+		if (red == blue) {
+			throw new IllegalStateException("must be different players (simply create two instances)");
+		}
+		var board = new Stone[WIDTH * HEIGHT];
+		red.initialize(Arrays.copyOf(board, board.length), Stone.RED);
+		blue.initialize(Arrays.copyOf(board, board.length), Stone.BLUE);
+		var lastMove = NOMOVE;
+		var currentPlayer = red;
+		for (int round = 0; round < board.length; round++) {
+			var currentColor = currentPlayer == red ? Stone.RED : Stone.BLUE;
+			System.out.println(HumanPlayer.toPrettyString(board) + currentColor + " to play next...");
+			lastMove = currentPlayer.play(lastMove);
+			if (lastMove < 0 || lastMove >= WIDTH * HEIGHT) {
+				throw new IllegalStateException("move is outside of valid range: " + lastMove);
+			}
+			if (board[lastMove] != null) {
+				throw new IllegalStateException("position " + lastMove + " is already occupied @" + toDebugString(board));
+			}
+			if (lastMove > WIDTH && board[lastMove - WIDTH] == null) {
+				throw new IllegalStateException("position " + lastMove + " is mid-air @" + toDebugString(board));
+			}
+			board[lastMove] = currentColor;
+			if (isWinning(board, currentColor)) {
+				System.out.println(
+						HumanPlayer.toPrettyString(board) + "...and the winner is: " + currentColor + " @ " + toDebugString(board));
+				return currentPlayer;
+			}
+			currentPlayer = currentPlayer == red ? blue : red;
+		}
+		System.out.println(HumanPlayer.toPrettyString(board) + "...it's a DRAW @ " + toDebugString(board));
+		return null; // null implies a draw
+	}
+
+	boolean isWinning(Stone[] board, Stone forColor) {
+		// TODO: provide an implementation
+		throw new IllegalStateException("Not implemented yet");
+	}
+
+	public enum Stone {
+		RED, BLUE;
+
+		public Stone opponent() {
+			return this == RED ? BLUE : RED;
+		}
+	}
+
+	public interface Connect4Player {
+
+		/**
+		 * Called before the game starts and guaranteed to only be called once per livetime of the player.
+		 *
+		 * @param board the starting board, usually an empty board.
+		 * @param colorToPlay the color of this player
+		 */
+		void initialize(Stone[] board, Stone colorToPlay);
+
+		/**
+		 * Perform a next move, will only be called if the Game is not over yet.
+		 * Each player has to keep an internal state of the 4x7 board, wher the 0-index is on the bottom row.
+		 * The index-layout looks as:
+		 * <pre>
+		 * 21 22 23 24 25 26 27
+		 * 14 15 16 17 18 19 20
+		 *  7  8  9 10 11 12 13
+		 *  0  1  2  3  4  5  6
+		 * </pre>
+		 *
+		 * @param opponendPlayed the last index where the opponent played to (in range 0 - width*height exclusive)
+		 * or -1 if this is the first move.
+		 * @return an index to play to (in range 0 - width*height exclusive)
+		 */
+		int play(int opponendPlayed);
+	}
+
+	/**
+	 * An abstract helper class to keep track of a board (and whatever we or the opponent played).
+	 */
+	public abstract static class DefaultPlayer implements Connect4Player {
+
+		Stone[] board;
+
+		Stone myColor;
+
+		@Override
+		public void initialize(Stone[] board, Stone colorToPlay) {
+			this.board = board;
+			myColor = colorToPlay;
+		}
+
+		@Override
+		public int play(int opponendPlayed) {
+			if (opponendPlayed != NOMOVE) {
+				board[opponendPlayed] = myColor.opponent();
+			}
+			var playTo = play();
+			board[playTo] = myColor;
+			return playTo;
+		}
+
+		/**
+		 * Givent the current {@link #board}, find a suitable position-index to play to.
+		 * @return the position to play to as defined by {@link Connect4Player#play(int)}.
+		 */
+		abstract int play();
+
+	}
+
+	public static class HumanPlayer extends DefaultPlayer {
+
+		static String toPrettyString(Stone[] board) {
+			var sb = new StringBuilder();
+			for (int r = HEIGHT - 1; r >= 0; r--) {
+				for (int c = 0; c < WIDTH; c++) {
+					var index = r * WIDTH + c;
+					if (board[index] == null) {
+						if (index < WIDTH || board[index - WIDTH] != null) {
+							sb.append("\033[37m" + index + "\033[0m ");
+							if (index < 10) {
+								sb.append(" ");
+							}
+						} else {
+							sb.append("\033[37m.\033[0m  ");
+						}
+					} else if (board[index] == Stone.RED) {
+						sb.append("\033[1;31mX\033[0m  ");
+					} else {
+						sb.append("\033[1;34mO\033[0m  ");
+					}
+				}
+				sb.append("\n");
+			}
+			return sb.toString();
+		}
+		@Override
+		int play() {
+			System.out.println("where to to put the next " + myColor + "?");
+			var scanner = new Scanner(System.in, StandardCharsets.UTF_8);
+			return Integer.parseInt(scanner.nextLine());
+		}
+
+	}
+
+	public static class GreedyPlayer extends DefaultPlayer {
+
+		@Override
+		int play() {
+			for (int c = 0; c < WIDTH; c++) {
+				for (int r = 0; r < HEIGHT; r++) {
+					var index = r * WIDTH + c;
+					if (board[index] == null) {
+						return index;
+					}
+				}
+			}
+			throw new IllegalStateException("cannot play at all");
+		}
+	}
+
+}
diff --git a/minmax-java/src/test/java/ch/bbw/m411/connect4/Connect4MainTest.java b/minmax-java/src/test/java/ch/bbw/m411/connect4/Connect4MainTest.java
new file mode 100644
index 0000000..b0c21c5
--- /dev/null
+++ b/minmax-java/src/test/java/ch/bbw/m411/connect4/Connect4MainTest.java
@@ -0,0 +1,64 @@
+package ch.bbw.m411.connect4;
+
+import java.util.List;
+
+import org.assertj.core.api.AbstractBooleanAssert;
+import org.assertj.core.api.WithAssertions;
+import org.junit.jupiter.api.Test;
+
+class Connect4MainTest implements WithAssertions {
+
+	protected Connect4ArenaMain newInstance() {
+		return new Connect4ArenaMain();
+	}
+
+	Connect4ArenaMain.Stone[] fromString(String boardStr) {
+		var board = boardStr.codePoints()
+				.map(Character::toLowerCase)
+				.filter(x -> List.of('x', 'o', '.')
+						.contains((char) x))
+				.mapToObj(x -> x == 'x' ? Connect4ArenaMain.Stone.RED : (x == 'o' ? Connect4ArenaMain.Stone.BLUE : null))
+				.toArray(Connect4ArenaMain.Stone[]::new);
+		assertThat(board).hasSize(Connect4ArenaMain.WIDTH * Connect4ArenaMain.HEIGHT);
+		return board;
+	}
+
+	AbstractBooleanAssert<?> assertThatXWin(String boardStr) {
+		var board = fromString(boardStr);
+		return assertThat(newInstance().isWinning(board, Connect4ArenaMain.Stone.RED)).as(Connect4ArenaMain.toDebugString(board));
+	}
+
+	@Test
+	void isWin() {
+		assertThatXWin("xxxx... ....... ....... .......").isTrue();
+		assertThatXWin(".xxxx.. ....... ....... .......").isTrue();
+		assertThatXWin("..xxxx. ....... ....... .......").isTrue();
+		assertThatXWin("...xxxx ....... ....... .......").isTrue();
+		assertThatXWin("...x... ...x... ...x... ...x...").isTrue();
+		assertThatXWin("......x ......x ......x ......x").isTrue();
+		assertThatXWin("xooo... .xoo... ..xo... ...x...").isTrue();
+		assertThatXWin(".ooxo.. .oxoo.. .xxxx.. .......").isTrue();
+		assertThatXWin(".ooxo.x .oxoo.. .ooxx.. .xxxx..").isTrue();
+		assertThatXWin("oooo... xxxx... ....... .......").isTrue();
+	}
+
+	@Test
+	void noWin() {
+		assertThatXWin("....... ....... ....... .......").isFalse();
+		assertThatXWin("xxx.xx. ....... ....... .......").isFalse();
+		assertThatXWin("xxx.xxx xxx.xxx xxx.xxx .......").isFalse();
+		assertThatXWin("xx.x.xx xx.x.xx xx.x.xx .......").isFalse();
+		assertThatXWin("ooo.ooo xxx.xxx xxx.xxx xxx.xxx").isFalse();
+		assertThatXWin("oo.o.oo xx.x.xx xx.x.xx xx.x.xx").isFalse();
+		assertThatXWin("oooo... ....... ....... .......").isFalse();
+		assertThatXWin("xxx.xx. xxx.xx. xxx.... o......").isFalse();
+		assertThatXWin("xxxo... x.x.... x.o.... o.x....").isFalse();
+	}
+
+	@Test
+	void inAGreedyBattleTheFirstPlayerWillWin() {
+		var red = new Connect4ArenaMain.GreedyPlayer();
+		var blue = new Connect4ArenaMain.GreedyPlayer();
+		assertThat(newInstance().play(red, blue)).isSameAs(red);
+	}
+}