First, let’s create an event called 'Spike' that uses a spike graphic. Set it to run in parallel with a single conditional branch: checkCollide(this._eventId, 'player', 15). This will check every 15 frames if the player is standing on the spike event. If they are, the condition will return true. The rest is simple: add the 'Increase/Decrease Player HP' command and reduce the player’s HP by the amount of damage you want them to take.
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| Adding a number (15) to checkCollide allows it to keep returning true unlimited of times |
To allow other events to take damage, create a custom notetag (such as <haha>) and add it to the 'player' section. Now, the spike will check for any event with the <haha> notetag instead of just the player. Make sure to also change the 'Increase/Decrease Player HP' command to 'Increase/Decrease Enemy HP' to reflect this.