🏃

Setup & the Runner

Template + a player locked to the ground line

Active

🎯

Goal for this step

Standard setup with a player that runs along the bottom of the screen.

1New game.py with the usual template (800×480).
2Player Rect at the bottom: y fixed at 430, x moves with arrows at speed 8, this game is about horizontal reflexes.
3Clamp to the screen edges (Episode 1 skill!).
4Draw the player teal.

game.py

player = pygame.Rect(380, 430, 40, 40)

keys = pygame.key.get_pressed()
if keys[pygame.K_LEFT]:
    player.x -= 8
if keys[pygame.K_RIGHT]:
    player.x += 8
player.x = max(0, min(800 - player.width, player.x))

✏️

Fill in the Blanks

+15 XP

This game locks the player’s position and only moves along . The clamp uses max and together.

🧠

Knowledge Check

+15 XP

Player speed is 8 here vs 5 in the platformer. What does higher speed change?

ANothing noticeable

BThe game feel, faster reactions possible, so falling objects can be faster too

CThe window size

⏲️

The Spawn Timer

Spawn a new falling object every 40 frames

Locked

🎯

Goal for this step

Build a frame-counting timer that spawns falling gems into a list.

1Falling things live in a list. Each is a small dictionary: {"rect": Rect, "kind": "gem"}.
2A spawn timer is just a counter: spawn_timer += 1 each frame; at 40, spawn and reset to 0.
340 frames at 60 FPS ≈ 0.66 seconds between spawns.
4Move every object down each frame, and delete the ones past the bottom (the [:] copy trick).

game.py

import random
things = []
spawn_timer = 0

# inside the loop:
spawn_timer += 1
if spawn_timer >= 40:
    spawn_timer = 0
    things.append({
        "rect": pygame.Rect(random.randint(10, 766), -24, 24, 24),
        "kind": "gem"
    })

for t in things[:]:
    t["rect"].y += 5
    if t["rect"].y > 480:
        things.remove(t)

⌨️

Code Challenge

+20 XP

Complete the spawn timer:

game.py

spawn_timer += 1
if spawn_timer >= :
    spawn_timer = 
    things.({"rect": pygame.Rect(random.randint(10, 766), -24, 24, 24), "kind": "gem"})

💡 Hint: Spawn at the threshold, reset the counter, and add to the end of the list.

🧠

Knowledge Check

+15 XP

A frame-counter timer at 60 FPS with threshold 40 spawns roughly every…

A40 seconds

B0.66 seconds (40 ÷ 60)

C4 seconds

💣

Bombs: Weighted Random

25% of spawns are bombs, colour-coded danger

Locked

🎯

Goal for this step

Mix hazards into the spawn using weighted randomness.

1At spawn time, roll: kind = "bomb" if random.random() < 0.25 else "gem".
2random.random() gives 0.0-1.0, so < 0.25 is a 25% chance.
3Draw gems as teal diamonds (ellipse) and bombs as red circles, instant readability matters more than pretty.
4Tune the ratio: 40% bombs is panic, 10% is a snooze.

game.py

kind = "bomb" if random.random() < 0.25 else "gem"
things.append({
    "rect": pygame.Rect(random.randint(10, 766), -24, 24, 24),
    "kind": kind
})

# drawing:
for t in things:
    colour = (248, 113, 113) if t["kind"] == "bomb" else (77, 217, 224)
    pygame.draw.ellipse(screen, colour, t["rect"])

✏️

Fill in the Blanks

+15 XP

random.random() returns a number between 0.0 and . Checking < 0.25 gives a % chance of a bomb.

🧠

Knowledge Check

+15 XP

To make bombs rarer, 10%, the check becomes…

Arandom.random() < 0.10

Brandom.random() > 0.10

Crandom.randint(0, 10)

💥

Catch or Boom

Gems score, bombs cost a life

Locked

🎯

Goal for this step

Handle both collision outcomes and show score + lives.

1Loop the list (copy!), test colliderect with the player.
2Gem → score += 1, remove. Bomb → lives -= 1, remove.
3Missing a GEM is fine in this game, only bombs hurt. Different rules than Episode 1, notice the design choice!
4HUD: score left, hearts right.

game.py

score, lives = 0, 3

for t in things[:]:
    if player.colliderect(t["rect"]):
        if t["kind"] == "gem":
            score += 1
        else:
            lives -= 1
        things.remove(t)

⌨️

Code Challenge

+20 XP

Branch on what the player touched:

game.py

if player.colliderect(t["rect"]):
    if t["kind"] == :
        score += 1
    else:
        lives -= 
    things.(t)

💡 Hint: Compare the kind string; bombs cost one life; either way the object leaves the list.

🧠

Knowledge Check

+15 XP

In Episode 1 missing fruit lost a life; here only touching bombs does. Why vary the rules?

APygame versions differ

BDifferent rules create different tension, dodging vs catching are different skills

CLives are deprecated

📈

The Difficulty Curve

Faster falls, quicker spawns, more bombs over time

Locked

🎯

Goal for this step

Scale three difficulty knobs with score so the game always ends.

1Fall speed: 5 + score // 10.
2Spawn threshold: max(12, 40 - score // 2), faster spawns but never below 12 frames.
3Bomb chance: min(0.5, 0.25 + score * 0.005), creeps up, capped at 50%.
4A good arcade game is unbeatable by design, the difficulty curve guarantees an exciting death. Chase the high score instead!

game.py

fall_speed = 5 + score // 10
spawn_at = max(12, 40 - score // 2)
bomb_chance = min(0.5, 0.25 + score * 0.005)

if spawn_timer >= spawn_at:
    ...
    kind = "bomb" if random.random() < bomb_chance else "gem"

💡

min() and max() as caps and floors, the same clamp trick you use on positions works on difficulty too.

✏️

Fill in the Blanks

+15 XP

The spawn threshold has a floor of frames thanks to max(), and the bomb chance is capped at thanks to min().

🧠

Knowledge Check

+15 XP

Why cap the bomb chance at 50%?

APython floats stop at 0.5

BPast a point the game stops being hard-but-fair and becomes pure luck, caps protect the fun

CBombs are expensive to draw

🏅

High Score & Game Over

Persist the best score to a file, real saving!

Locked

🎯

Goal for this step

End the game cleanly and save the high score to disk so it survives restarts.

1Game over at 0 lives, freeze updates, show final score and press-R (Episode 1 pattern).
2Load the high score at startup from highscore.txt (default 0 if the file does not exist, use try/except).
3On game over, if score beats it: write the new record back to the file.
4That is genuine file I/O, your first persistent save data!

game.py

def load_highscore():
    try:
        with open("highscore.txt") as f:
            return int(f.read())
    except:
        return 0

def save_highscore(value):
    with open("highscore.txt", "w") as f:
        f.write(str(value))

high = load_highscore()

# when the game ends:
if score > high:
    high = score
    save_highscore(high)

⌨️

Code Challenge

+20 XP

Save a new record only when it IS a record:

game.py

if score > :
    high = score
    (high)

💡 Hint: Compare against the loaded best, then call the writing function.

🧠

Knowledge Check

+15 XP

Why wrap the file-reading in try/except?

AFiles are dangerous

BThe first ever run has no highscore.txt, except returns a default 0 instead of crashing

CTo make it faster

🎉🏆🎮✨🎉

Workshop Complete!

Spawn timers, object lists and a difficulty curve, you built a proper score-chaser. Episode 4 slows things down with a maze to solve.

Total XP

Level

Best Streak

Accuracy

▶ Episode 4: Maze Explorer →
⭐ View My Progress & Certificates

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