STEP 4 — Building a Full Decision System
STEP 4 — Building a Full Decision System (Your Game’s Brain Upgrade)
Alright, coder — this is the moment your game stops being a simple “if this, then that” machine and starts acting like it actually understands what’s happening.
This step is all about combining everything:
- conditions
- comparisons
- logical operators
- lists
…to build a decision system —the same kind of logic that powers battles, quests, shops,
puzzles, and every “choose your path” moment in games.
Let’s build one.
1. Scenario — A Player Encounters an Enemy
Your game needs to decide:
- Can the player fight?
- Should they run?
- Do they have the right items?
- Are they strong enough?
This is where your game’s brain kicks in.
2. Combining Conditions + Lists + Logic
Here’s a full decision system in action:
health = 45
inventory = ["sword", "potion", "map"]
enemy = "goblin"
if health > 50 and "sword" in inventory:
print("You engage the goblin confidently.")
elif health <= 50 and "potion" in inventory:
print("You drink a potion before fighting.")
elif "sword" not in inventory:
print("You have no weapon. You run away.")
else:
print("You decide to avoid the fight for now.")
Click Run to execute.
Your game is now thinking like this:
- “Health is good AND you have a sword? Go fight.”
- “Health is low BUT you have a potion? Heal first.”
- “No sword? Absolutely not, we’re leaving.”
- “Otherwise… maybe don’t fight a goblin today.”
This is real game logic — branching, reactive, and smart.
3. Why This Matters
This step unlocks:
- battle systems
- shop systems
- quest requirements
- puzzle logic
- dialogue choices
- branching storylines
Basically, everything that makes a game feel alive and responsive. You are now building the
core decision engine behind every modern game.
Practice (Your Turn!)
Mini-Challenge
You have:
health = 30
inventory = ["key", "torch"]
door_locked = True
Write a decision system:
- If the door is locked and the player has a key → print "You unlock the door."
- If the door is locked and the player does NOT have a key → print "The door won't budge."
- If the door is not locked → print "You open the door easily."
Write code and Run.

