Gamemaker Studio 2 Gml

Why: You tried to use a variable in the Step Event before it was created in the Create Event. Fix: Initialize everything in the Create Event, even if it's just to undefined or 0.

If you override an event in a child object, the parent's code won't run unless you call this.

You can also use the Collision event (e.g., Collision with obj_lava): gamemaker studio 2 gml

hp -= 10;
x = checkpoint_x;
y = checkpoint_y;

// Step Event
var key_left = keyboard_check(vk_left);
var key_right = keyboard_check(vk_right);
var key_jump = keyboard_check_pressed(vk_space); // true only for one frame
// Custom keys (ASCII)
var key_attack = keyboard_check(ord('X'));

Use this for HUD (health, ammo, score).

// Draw GUI Event
draw_set_color(c_black);
draw_text(10, 10, "Score: " + string(global.score));
draw_text(10, 30, "Lives: " + string(global.lives));

// Modern Map using Struct
var inventory = 
    gold: 150,
    weapons: ["Dagger", "Bow"]
;
inventory.gold += 50; // Easy access

Structs are GML’s version of JSON-like objects. They are lightweight and perfect for save files or stat containers. Why: You tried to use a variable in

// Create a struct
var player_stats = 
    level: 5,
    hp: 100,
    attack: function(enemy) 
        enemy.hp -= 10;
;
// Call the function inside the struct
player_stats.attack(some_enemy);