Forest area is not available in current version, but there's forest environment in the mist tower, try it
It's random now in the latest version, but in the version 0.3.0 the forest enviroment usually appears at very first floor. Btw be aware of the mobs that do not exist in main route such as cockatrice, tentacle trap and karakasa youkai, they are horrible enemies especially when you are lack of ranged weapon in the tower.
potions are very good, a bat n spray (that isnt green) would help too. the only other things i can think of is save the sprays for ghost melee-immune/tanky enemies, save the melee for enemies that wont die to a knife or a slide, always try to look for the closet room in the city areas if you need it, and always spam swipe or slide when going to a new room incase an enemy is right there. all that and the game feels genuinely easier with a controller lol.