diff --git a/generic_waf2_test_output.txt b/generic_waf2_test_output.txt
index c903259..b284487 100644
--- a/generic_waf2_test_output.txt
+++ b/generic_waf2_test_output.txt
@@ -1,7 +1,7 @@
 Error, no card to draw exists
 Error, can not get resources: game not started
 Error, could not build item
-Error, unknown command
+Error, invalid build command
 Error, can not get buildings: game not started
 Error, can not get buildable items: game not started
 Error, not expecting dice roll
@@ -14,7 +14,7 @@ EMPTY
 wood
 wood
 Error, could not build item
-Error, unknown command
+Error, invalid build command
 EMPTY
 EMPTY
 Error, not expecting dice roll
@@ -29,7 +29,7 @@ spider
 Error, roll dice, please
 wood
 Error, awaiting dice roll, can not build
-Error, unknown command
+Error, invalid build command
 EMPTY
 Error, can not get buildable items: awaiting dice roll
 Error, unexpected dice size
@@ -39,7 +39,7 @@ snake
 Error, roll dice, please
 wood
 Error, awaiting dice roll, can not build
-Error, unknown command
+Error, invalid build command
 EMPTY
 Error, can not get buildable items: awaiting dice roll
 Error, unexpected dice size
@@ -49,7 +49,7 @@ tiger
 Error, roll dice, please
 wood
 Error, awaiting dice roll, can not build
-Error, unknown command
+Error, invalid build command
 EMPTY
 Error, can not get buildable items: awaiting dice roll
 Error, unexpected dice size
diff --git a/src/edu/kit/informatik/cardgame/ui/command/Build.java b/src/edu/kit/informatik/cardgame/ui/command/Build.java
index b2c7c38..09d52c7 100644
--- a/src/edu/kit/informatik/cardgame/ui/command/Build.java
+++ b/src/edu/kit/informatik/cardgame/ui/command/Build.java
@@ -12,7 +12,7 @@ import java.util.regex.Pattern;
 import static edu.kit.informatik.cardgame.ui.command.CommandFactory.BUILD;
 
 public final class Build extends Command {
-    private static final Pattern BUILD_ARGUMENT = Pattern.compile(BUILD + "(\\w+)");
+    private static final Pattern BUILD_ARGUMENT = Pattern.compile(" (\\w+)");
 
     private Item item;
 
@@ -31,7 +31,7 @@ public final class Build extends Command {
         if (input == null || !input.startsWith(BUILD)) {
             throw new InvalidInputException("unknown command");
         }
-        final Matcher matcher = Build.BUILD_ARGUMENT.matcher(input);
+        final Matcher matcher = Build.BUILD_ARGUMENT.matcher(input.substring(BUILD.length()));
         if (!matcher.matches()) {
             throw new InvalidInputException("invalid build command");
         }
diff --git a/src/edu/kit/informatik/cardgame/ui/command/CommandFactory.java b/src/edu/kit/informatik/cardgame/ui/command/CommandFactory.java
index 8fc0cdd..d542d52 100644
--- a/src/edu/kit/informatik/cardgame/ui/command/CommandFactory.java
+++ b/src/edu/kit/informatik/cardgame/ui/command/CommandFactory.java
@@ -2,27 +2,27 @@ package edu.kit.informatik.cardgame.ui.command;
 
 import edu.kit.informatik.cardgame.ui.InvalidInputException;
 
-import java.util.HashMap;
 import java.util.Map;
+import java.util.TreeMap;
 import java.util.function.Supplier;
 
 /**
  * Factory used to parse user input into commands.
  *
  * @author Arne Keller
- * @version 1.0
+ * @version 1.1
  */
 public final class CommandFactory {
     public static final String START = "start";
     public static final String DRAW = "draw";
     public static final String LIST_RESOURCES = "list-resources";
-    public static final String BUILD = "build ";
+    public static final String BUILD = "build";
     public static final String LIST_BUILDINGS = "list-buildings";
     public static final String BUILDABLE = "build?";
     public static final String ROLL_DICE = "rollD";
     public static final String RESET = "reset";
 
-    private static final Map<String, Supplier<Command>> COMMANDS = new HashMap<>();
+    private static final TreeMap<String, Supplier<Command>> COMMANDS = new TreeMap<>();
 
     static {
         // initialize registered commands
@@ -50,8 +50,10 @@ public final class CommandFactory {
      * @throws InvalidInputException if user input is invalid
      */
     public static Command getCommand(String input) throws InvalidInputException {
-        Supplier<Command> commandSupplier = COMMANDS.entrySet().stream()
-                .filter(entry -> input.startsWith(entry.getKey())).map(Map.Entry::getValue)
+        Supplier<Command> commandSupplier = COMMANDS
+                .descendingKeySet().stream()
+                .filter(input::startsWith)
+                .map(COMMANDS::get)
                 .findFirst().orElse(null);
         if (commandSupplier != null) {
             Command command = commandSupplier.get();