Method isProgeny

src/main/java/fieldbox/boxes/plugins/Variant.java:536–540

(Box x, Variant me)

	}

	private boolean isProgeny(Box x, Variant me) {
		return me.breadthFirstAll(me.downwards())
			.filter(y -> y != this)
			.anyMatch(y -> y == x);
	}


	public void loaded() {