const heat = game.user.getFlag(`world`, `heatMeter`) ?? 0;

let r = new Roll(`1d6`);
await r.evaluate();
const reduceBy = r.total;

const reducedHeat = Math.max(0, heat - reduceBy);
game.user.setFlag(`world`, `heatMeter`, reducedHeat);

const chatData = ChatMessage.applyRollMode(
	{
		content: `<p>Removed ${reduceBy} Heat.</p><p>Current Heat total after removal: ${reducedHeat}</p>`,
	},
);
await ChatMessage.implementation.create(chatData);