diff --git a/docs/star-seek.md b/docs/star-seek.md
index 07bb013..c0661cd 100644
--- a/docs/star-seek.md
+++ b/docs/star-seek.md
@@ -5,7 +5,17 @@ The star seek mini-game uses gaze + head position to collect stars that appear a
 ## Main objects / values to edit during play testing
 
 - **StarSeekManager**: values related to the overall win condition of the game
-  - Game time limit
+  - Minimum game time limit (seconds)
+  - Maximum game time limit (seconds)
+  - How many seconds to increase the time limit, if the upgrade rate is met
+  - Upgrade rate: (number of stars collected / game time limit) i.e. average stars collected per second, must be above this value to increase the time limit of future games.
+  - Number of games in a row that must meet the upgrade rate
+
+- **StarGenerator**: values related to spawning stars
+  - Min distance between stars and the edge of the screen
+  - Number of rows + columns in star spawn grid
+  - Grid positions to exclude from star spawning (e.g. those that overlap with UI elements)
+  - Min distance between spawned stars
 
 - **Prefabs/StarSeekStar**: values related to 'locking on' to a star
   - Time required to collect a star (with both gaze + head pose crosshair aligned)
diff --git a/projects/AstroBalance/Assets/Scenes/StarSeek.unity b/projects/AstroBalance/Assets/Scenes/StarSeek.unity
index c7e6d3a..f81c42f 100644
--- a/projects/AstroBalance/Assets/Scenes/StarSeek.unity
+++ b/projects/AstroBalance/Assets/Scenes/StarSeek.unity
@@ -151,7 +151,11 @@ MonoBehaviour:
   scoreText: {fileID: 730211112}
   timer: {fileID: 740804264}
   winScreen: {fileID: 159571674}
-  timeLimit: 120
+  minTimeLimit: 60
+  maxTimeLimit: 180
+  timeLimitIncrement: 60
+  timeLimitUpgradeRate: 0.3
+  nGamesToUpgrade: 3
 --- !u!4 &5281182
 Transform:
   m_ObjectHideFlags: 0
@@ -407,6 +411,14 @@ MonoBehaviour:
   m_Name: 
   m_EditorClassIdentifier: 
   starPrefab: {fileID: 7594402928058972626, guid: 8a1f0e2645d064545887a1468814863e, type: 3}
+  edgeOffset: 1
+  nRows: 4
+  nColumns: 6
+  gridPositionsToExclude:
+  - {x: 0, y: 3}
+  - {x: 5, y: 3}
+  - {x: 5, y: 0}
+  minDistance: 7
 --- !u!4 &609642610
 Transform:
   m_ObjectHideFlags: 0
diff --git a/projects/AstroBalance/Assets/Scripts/SaveData.cs b/projects/AstroBalance/Assets/Scripts/SaveData.cs
index 1b90890..d51c487 100644
--- a/projects/AstroBalance/Assets/Scripts/SaveData.cs
+++ b/projects/AstroBalance/Assets/Scripts/SaveData.cs
@@ -45,6 +45,15 @@ public T GetLastGameData()
         return savedGames.LastOrDefault();
     }
 
+    /// <summary>
+    /// Get data from the last n played games.
+    /// </summary>
+    /// <param name="nGames">Number of games to retrieve</param>
+    public IEnumerable<T> GetLastNGamesData(int nGames)
+    {
+        return savedGames.TakeLast(nGames);
+    }
+
     public void Save()
     {
         string json = JsonUtility.ToJson(this, true);
diff --git a/projects/AstroBalance/Assets/Scripts/StarSeek/LockedOn.cs b/projects/AstroBalance/Assets/Scripts/StarSeek/LockedOn.cs
index 1afaadc..9e7b522 100644
--- a/projects/AstroBalance/Assets/Scripts/StarSeek/LockedOn.cs
+++ b/projects/AstroBalance/Assets/Scripts/StarSeek/LockedOn.cs
@@ -5,7 +5,7 @@
 public class LockedOn : MonoBehaviour
 {
     [SerializeField, Tooltip("Number of seconds required to collect star")]
-    private float doubleLockTime = 2;
+    private float doubleLockTime = 0.5f;
 
     [SerializeField, Tooltip("Particle system to be shown on star collection")]
     private GameObject collectEffect;
diff --git a/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekGenerator.cs b/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekGenerator.cs
index c338705..bb73867 100644
--- a/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekGenerator.cs
+++ b/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekGenerator.cs
@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Unity.VisualScripting;
@@ -8,47 +9,126 @@ public class StarSeekGenerator : MonoBehaviour
     [SerializeField, Tooltip("Star prefab to generate")]
     private GameObject starPrefab;
 
-    private List<Vector2> spawnLocations = new List<Vector2>
-    {
-        new Vector2(-8, 0), // left
-        new Vector2(8, 0), // right
-        new Vector2(0, 4), // up
-        new Vector2(0, -4), // down
-    };
+    [SerializeField, Tooltip("Min distance between stars and the edge of the screen.")]
+    private int edgeOffset = 1;
+
+    [SerializeField, Tooltip("Number of rows in star spawn grid")]
+    private int nRows = 4;
+
+    [SerializeField, Tooltip("Number of columns in star spawn grid")]
+    private int nColumns = 6;
+
+    [
+        SerializeField,
+        Tooltip(
+            "Positions in the spawn grid to exclude (e.g. overlapping with UI elements). (0, 0) is the bottom left star and (nColumns - 1, nRows - 1) is the top right star."
+        )
+    ]
+    private List<Vector2> gridPositionsToExclude = new List<Vector2>();
+
+    [SerializeField, Tooltip("Min distance between spawned stars"), Range(0, 9)]
+    private int minDistance = 7;
+
+    private List<Vector2> spawnLocations = new List<Vector2>();
     private GameObject currentStar;
-    private int lastSpawnLocationIndex = -1;
+    private bool firstSpawn = true;
+    private Vector2 lastSpawnLocation;
 
     // Start is called once before the first execution of Update after the MonoBehaviour is created
     void Start()
     {
-        spawnStar();
+        FillSpawnLocations();
+        SpawnStar();
     }
 
-    private void spawnStar()
+    /// <summary>
+    /// Create a grid of spawn locations, excluding those in 'gridPositionsToExclude'
+    /// </summary>
+    private void FillSpawnLocations()
     {
-        int chosenIndex;
-        if (lastSpawnLocationIndex == -1)
+        Vector2 gridBottomLeft =
+            Camera.main.ViewportToWorldPoint(new Vector2(0, 0))
+            + new Vector3(edgeOffset, edgeOffset, 0);
+        Vector2 gridTopRight =
+            Camera.main.ViewportToWorldPoint(new Vector2(1, 1))
+            - new Vector3(edgeOffset, edgeOffset, 0);
+
+        float xSpacing = (gridTopRight.x - gridBottomLeft.x) / (nColumns - 1);
+        float ySpacing = (gridTopRight.y - gridBottomLeft.y) / (nRows - 1);
+
+        float xLocation = gridBottomLeft.x;
+        float yLocation = gridBottomLeft.y;
+        for (int i = 0; i < nColumns; i++)
+        {
+            for (int j = 0; j < nRows; j++)
+            {
+                AddSpawnLocation(new Vector2(xLocation, yLocation), new Vector2(i, j));
+                yLocation += ySpacing;
+            }
+
+            xLocation += xSpacing;
+            yLocation = gridBottomLeft.y;
+        }
+    }
+
+    /// <summary>
+    /// Add spawn location, if it is not in 'gridPositionsToExclude'
+    /// </summary>
+    /// <param name="worldPosition">Unity world position to spawn</param>
+    /// <param name="gridPosition">Position in grid (column, row)</param>
+    private void AddSpawnLocation(Vector2 worldPosition, Vector2 gridPosition)
+    {
+        foreach (Vector2 excludeLocation in gridPositionsToExclude)
+        {
+            if (gridPosition == excludeLocation)
+            {
+                return;
+            }
+        }
+
+        spawnLocations.Add(worldPosition);
+    }
+
+    private void SpawnStar()
+    {
+        List<Vector2> possibleLocations = new List<Vector2>();
+
+        if (firstSpawn)
         {
             // If this is our first time generating a star, choose from all locations
-            chosenIndex = Random.Range(0, spawnLocations.Count);
+            possibleLocations = spawnLocations;
+            firstSpawn = false;
         }
         else
         {
-            // If we have spawned a star previously, make sure it moves to a new location
-            IEnumerable<int> indexes = Enumerable.Range(0, spawnLocations.Count);
-            indexes = indexes.Except(new int[] { lastSpawnLocationIndex });
+            // If we have spawned a star previously, choose a new location that is at
+            // least minDistance away
+            foreach (Vector2 spawnLocation in spawnLocations)
+            {
+                float distance = Vector2.Distance(spawnLocation, lastSpawnLocation);
+                if (distance >= minDistance)
+                {
+                    possibleLocations.Add(spawnLocation);
+                }
+            }
+        }
 
-            chosenIndex = indexes.ElementAt(Random.Range(0, indexes.Count()));
+        if (possibleLocations.Count() == 0)
+        {
+            throw new InvalidOperationException(
+                "No valid spawn locations available - try decreasing minDistance."
+            );
         }
 
-        // Spawn a star at the randomly chosen location
-        Vector2 chosenLocation = spawnLocations.ElementAt(chosenIndex);
+        // Spawn a star at a randomly chosen location
+        int chosenIndex = UnityEngine.Random.Range(0, possibleLocations.Count);
+        Vector2 chosenLocation = possibleLocations.ElementAt(chosenIndex);
         currentStar = Instantiate(
             starPrefab,
             new Vector3(chosenLocation.x, chosenLocation.y, 0),
             Quaternion.identity
         );
-        lastSpawnLocationIndex = chosenIndex;
+        lastSpawnLocation = chosenLocation;
     }
 
     // Update is called once per frame
@@ -56,7 +136,7 @@ void Update()
     {
         if (currentStar.IsDestroyed())
         {
-            spawnStar();
+            SpawnStar();
         }
     }
 }
diff --git a/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekManager.cs b/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekManager.cs
index 0a3789f..93b95a5 100644
--- a/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekManager.cs
+++ b/projects/AstroBalance/Assets/Scripts/StarSeek/StarSeekManager.cs
@@ -1,3 +1,5 @@
+using System.Collections.Generic;
+using System.Linq;
 using TMPro;
 using UnityEngine;
 
@@ -12,10 +14,33 @@ public class StarSeekManager : MonoBehaviour
     [SerializeField, Tooltip("Screen shown upon winning the game")]
     private GameObject winScreen;
 
-    [SerializeField, Tooltip("Game time limit in seconds")]
-    private int timeLimit = 120;
+    [SerializeField, Tooltip("Minimum game time limit in seconds")]
+    private int minTimeLimit = 60;
+
+    [SerializeField, Tooltip("Maximum game time limit in seconds")]
+    private int maxTimeLimit = 180;
+
+    [SerializeField, Tooltip("Time limit increase if timeLimitUpgradeRate is met")]
+    private int timeLimitIncrement = 60;
+
+    [
+        SerializeField,
+        Tooltip(
+            "(number of stars collected / game time limit) i.e. average stars collected per second - must be above this value to increase the time limit of future games."
+        )
+    ]
+    private float timeLimitUpgradeRate = 0.3f;
+
+    [
+        SerializeField,
+        Tooltip(
+            "Number of games in a row that must meet timeLimitUpgradeRate to increase the time limit"
+        )
+    ]
+    private int nGamesToUpgrade = 3;
 
     private int score;
+    private int timeLimit;
     private TextMeshProUGUI winText;
     private bool gameActive = true;
     private StarSeekData gameData;
@@ -25,12 +50,62 @@ public class StarSeekManager : MonoBehaviour
     void Start()
     {
         winText = winScreen.GetComponentInChildren<TextMeshProUGUI>();
+        ChooseGameTimeLimit();
+
         score = 0;
         scoreText.text = score.ToString();
         gameData = new StarSeekData();
         timer.StartCountdown(timeLimit);
     }
 
+    /// <summary>
+    /// Load previous game data (if any), and choose time limit for this game based
+    /// on prior perfomance.
+    /// </summary>
+    private void ChooseGameTimeLimit()
+    {
+        SaveData<StarSeekData> saveData = new(saveFilename);
+        IEnumerable<StarSeekData> lastNGamesData = saveData.GetLastNGamesData(nGamesToUpgrade);
+
+        if (lastNGamesData.Count() < nGamesToUpgrade)
+        {
+            SetTimeLimit(minTimeLimit);
+            return;
+        }
+
+        // Upgrade if all the last n games have the same time limit + meet the upgrade
+        // rate. If it's a mix of time limits, then we haven't played enough games at
+        // this level yet to progress.
+        int nGamesAtUpgradeRate = 0;
+        bool allSameTimeLimit = true;
+        int lastTimeLimit = lastNGamesData.Last().timeLimitSeconds;
+
+        foreach (StarSeekData data in lastNGamesData)
+        {
+            float starRate = (float)data.nStarsCollected / (float)data.timeLimitSeconds;
+
+            if (data.timeLimitSeconds != lastTimeLimit)
+            {
+                allSameTimeLimit = false;
+                break;
+            }
+
+            if (starRate >= timeLimitUpgradeRate)
+            {
+                nGamesAtUpgradeRate++;
+            }
+        }
+
+        if (allSameTimeLimit && nGamesAtUpgradeRate >= nGamesToUpgrade)
+        {
+            SetTimeLimit(lastTimeLimit + timeLimitIncrement);
+        }
+        else
+        {
+            SetTimeLimit(lastTimeLimit);
+        }
+    }
+
     // Update is called once per frame
     void Update()
     {
@@ -77,4 +152,20 @@ private void SaveGameData()
         SaveData<StarSeekData> saveData = new(saveFilename);
         saveData.SaveGameData(gameData);
     }
+
+    private void SetTimeLimit(int limit)
+    {
+        if (limit > maxTimeLimit)
+        {
+            timeLimit = maxTimeLimit;
+        }
+        else if (limit < minTimeLimit)
+        {
+            timeLimit = minTimeLimit;
+        }
+        else
+        {
+            timeLimit = limit;
+        }
+    }
 }