diff --git a/cmd/rove/main.go b/cmd/rove/main.go
index 674428e..5d5100f 100644
--- a/cmd/rove/main.go
+++ b/cmd/rove/main.go
@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"io/ioutil"
-	"math"
 	"os"
 	"path"
 
@@ -175,13 +174,7 @@ func InnerMain(command string) error {
 
 		} else {
 			// Print out the radar
-			num := int(math.Sqrt(float64(len(response.Tiles))))
-			for j := num - 1; j >= 0; j-- {
-				for i := 0; i < num; i++ {
-					fmt.Printf("%d", response.Tiles[i+num*j])
-				}
-				fmt.Print("\n")
-			}
+			game.PrintTiles(response.Tiles)
 		}
 
 	case "rover":
diff --git a/pkg/game/world.go b/pkg/game/world.go
index a0a24b7..a4d1912 100644
--- a/pkg/game/world.go
+++ b/pkg/game/world.go
@@ -2,6 +2,7 @@ package game
 
 import (
 	"fmt"
+	"math"
 	"math/rand"
 	"strings"
 	"sync"
@@ -68,8 +69,8 @@ func (w *World) SpawnRover() (uuid.UUID, error) {
 
 	// Spawn in a random place near the origin
 	rover.Attributes.Pos = Vector{
-		w.Atlas.ChunkSize - (rand.Int() % (w.Atlas.ChunkSize * 2)),
-		w.Atlas.ChunkSize - (rand.Int() % (w.Atlas.ChunkSize * 2)),
+		w.Atlas.ChunkSize/2 - rand.Intn(w.Atlas.ChunkSize),
+		w.Atlas.ChunkSize/2 - rand.Intn(w.Atlas.ChunkSize),
 	}
 
 	// Seach until we error (run out of world)
@@ -91,6 +92,8 @@ func (w *World) SpawnRover() (uuid.UUID, error) {
 		return uuid.Nil, err
 	}
 
+	fmt.Printf("Spawned rover at %+v\n", rover.Attributes.Pos)
+
 	// Append the rover to the list
 	w.Rovers[rover.Id] = rover
 
@@ -152,9 +155,11 @@ func (w *World) WarpRover(id uuid.UUID, pos Vector) error {
 		}
 
 		// Update the world tile
-		// TODO: Make this (and other things) transactional
-		// TODO: Check this worldtile is free
-		if err := w.Atlas.SetTile(pos, TileRover); err != nil {
+		if tile, err := w.Atlas.GetTile(pos); err != nil {
+			return fmt.Errorf("coudln't get state of destination rover tile: %s", err)
+		} else if tile == TileRover {
+			return fmt.Errorf("Can't warp rover to occupied tile, check before warping")
+		} else if err := w.Atlas.SetTile(pos, TileRover); err != nil {
 			return fmt.Errorf("coudln't set rover tile: %s", err)
 		} else if err := w.Atlas.SetTile(i.Attributes.Pos, TileEmpty); err != nil {
 			return fmt.Errorf("coudln't clear old rover tile: %s", err)
@@ -345,6 +350,17 @@ func (w *World) ExecuteCommand(c *Command, rover uuid.UUID) (finished bool, err
 	return
 }
 
+// PrintTiles simply prints the input tiles directly for debug
+func PrintTiles(tiles []Tile) {
+	num := int(math.Sqrt(float64(len(tiles))))
+	for j := num - 1; j >= 0; j-- {
+		for i := 0; i < num; i++ {
+			fmt.Printf("%d", tiles[i+num*j])
+		}
+		fmt.Print("\n")
+	}
+}
+
 // RLock read locks the world
 func (w *World) RLock() {
 	w.worldMutex.RLock()
diff --git a/pkg/game/world_test.go b/pkg/game/world_test.go
index da19b40..d478b2c 100644
--- a/pkg/game/world_test.go
+++ b/pkg/game/world_test.go
@@ -107,8 +107,8 @@ func TestWorld_RadarFromRover(t *testing.T) {
 
 	// Warp the rovers into position
 	bpos := Vector{-3, -3}
-	assert.NoError(t, world.WarpRover(a, Vector{0, 0}), "Failed to warp rover")
 	assert.NoError(t, world.WarpRover(b, bpos), "Failed to warp rover")
+	assert.NoError(t, world.WarpRover(a, Vector{0, 0}), "Failed to warp rover")
 
 	// Spawn the world wall
 	err = world.Atlas.SpawnWalls()
@@ -129,6 +129,7 @@ func TestWorld_RadarFromRover(t *testing.T) {
 	// O------O-
 	// OR-----O-
 	// OOOOOOOO-
+	PrintTiles(radar)
 
 	// Test all expected values
 	assert.Equal(t, TileRover, radar[1+fullRange])