How to use the level/cells.js.Staircase function in level

this.adjustStat("hp", -1);
		}

		let item = this._level.getItem(this._xy);
		if (item) {
			log.add("%A is lying here.", item);
			if (!TUTORIAL.item) {
				log.add("To pick it up, press {#fff}Enter{}.");
				TUTORIAL.item = true;
			}
			return;
		}

		if (cell instanceof cells.Door) {
			log.add("You pass through %a.", cell);
		} else if (cell instanceof cells.Staircase) {
			log.add("%A is here.", cell);
			if (!TUTORIAL.staircase) {
				TUTORIAL.staircase = true;
				log.add("To use the staircase, press {#fff}Enter{}.");
			}
		}
	}