First off, buy the 3 shop items you won't get far without the weapons and the 3rd one will allow you to skip a rock. Saving you a lot of time and money in the end.
Hold shift to speed up combat.
B3:
Grab the keys open the door.
Fight the mouse and raven on the right path after you have opened the door. Get the potion.
Then go left and kill the slime and mouse to get the other potion.
Go down to the bottom of the floor and kill 1 of the slimes.
Then go up and to where you were and kill the slime next to the big heart.
Take the big heart and fight the red goblin. Then grab the little heart and go the bottom of the floor and kill the last to slimes to get the other little heart and some keys.
Then kill the raven and the mouse. Be cheeky and take the two attack upgrades from the other side where you don't have to fight.
Then go to the next floor.
B4:
Go to the right and open the door, take the two hearts and defense upgrade.
Fight the goblin and the slime to get the defense upgrade.
Fight the slime to get to the blue door and take the items.
Go out and proceed down the hallway, there is a mouse kill it and go to the reaper and fight it. Don't worry there is a heart hidden (somewhat) between them.
Destroy the rock and open the door on the left to get the attack upgrade and exit the floor.
B5:
Go to the left and before you fight the goblin open the yellow door right before it and grab the HP upgrade and small heart.
Then go to the next floor.
B6:
Take the first door to the north and kill the mouse to get the big heart and yellow key.
Go up to B5.
B5:
Open the door which leads to the shop and kill the two goblins.
Open the door to the upgradeshop and buy a +4 defense.
Kill the mouse to the left and the slime next to the fairy with the HP upgrade and take it.
Take the key and open the door to the little heart.
Go down to B6.
B6:
Just go to the right and kill the enemies standing in the way of the exit to B7.
B7:
Kill the mouse, the raven, and the slime. Take the key and use two yellow keys to get to the place with 3 yellow keys and 1 blue one.
Head all the way to B5 and take the one of the big hearts (and the keys) that were locked away in a blue door.
Go back to B7.
Open the yellow door on the right with the raven and blue key and kill the raven and take the key.
Use a blue key to get through and kill the reaper.
Open the door next to it for the upgrades.
Go to B5 and enter the room with the goblin and 3 upgrades (attack, defense, and health).
Take the last big heart of the floor in the upper left corner where you were earlier
Go to B3 and enter the rooms with the goblins and upgrades in them, it doesn't matter which of them you start with. Kill the raven guarding the 4 keys and take them.
Now head to B6 and open the door to the dinning room.
Go to the left and kill the two goblins so you can get the keys.
Get back up to B4 and open the blue door so you can enter two rooms, one with 2 yellow keys and the other has a grey key.
Go to the grey door and take the upgrades and keys.
Go back to the main hallway of the area. There are two paths requiring 3 yellow keys to proceed and skip the skeletons. Take the one on the left and kill the goblin. Then go the proceeding rooms for all the upgrades.
Go to B6 and kill the two reapers on the right of the dinning table.
Open the room with the raven and reaper in it, kill only the raven and take the defense upgrade. We are still 3 defense upgrades short of fighting the slime girl.
Kill the reaper and the ravens on the floor guarding an attack upgrade (killing red goblin only take 3 turns now instead of 4).
Go back to B7, kill the red goblin and exit the floor.
B8:
There is a girl on the right of the path. You can talk to her and she will unlock the 3 yellow doors. I let her, because... I dunno. It's just fun to do, plus you are a little short on keys

The yellow door with the 2 yellow keys in it should be a no brainer.
Go over the bridge where you get to a T section.
Open the door to the south and take the upgrade but don't fight.
Go back to the T section and head to the east instead where, kill the goblin.
In the 4 way (on path blocked by a rock cross section go up.
Follow the path till you get defense upgrade.
As you are now you can defeat the dragons with full HP, but the losses are too big.
Head to B5 and kill the slimes and the mouse to get the yellow key.
Go to B4, In the middle there should be 2 skeletons. You could use a blue key to get the defense upgrade without fighting the skeletons. But the net loss compared to the HP you lose while also getting a little heart is not worth it. If you open the yellow door on the right the net loss will be 2HP (it doesn't count armor in the HP loss) -112+100+10=-2. So we do that and take the upgrade.
Go back to B8 and go to where we left off.
After the bridge you will be given a choice between two paths (or cheesing out with the use of a blue key, though it's not neccesary at this point and we want to get the slime girl).
Take the path to the south in the "circle" in the upper right corner (square, you know what I mean). We take this path because of the net loss where the red goblin is stronger than the grey one.
Take the key to the left and don't forget to take the defense upgrade before you attack the goblin (I sometimes forget it in the rush). Kill the goblin and take the upgrades.
Go to B6, take the path we have cleared on the right and kill the raven to get the key.
Proceed that way to the slime girl as to not use any other keys than the blue required to enter her lair?Swamp? Whatever. Hurray for 0 dmg, 30g, a hentai scene with a cute woman, and some extra shield. GO HENTAI ARMOR xD
Go to B3 and kill you way to the room with the skeleton, keys, and upgrades.
Go to B5 and kill the skeleton and dragon and take all the good stuff.
Go to B4 and open the door with the 2 mice and little heart and take it.
Kill you way on the left on the same floor to get access to some keys. Open the room with the HP upgrade and the other room with two yellow keys.
Go to B8 and go south from the first T section where you will fight 2 skeletons and a dragon. You don't need to waste 2 keys to skip this fight.
B9:
Go either left or right first and take all the upgrades, if you take all the upgrades from one side you will have enough attack power for the next skeleton fight to only deal 48dmg which will be absorbed by the 55 armor.
Go back to B8 and fight your way to the little heart.
Go to B6, fight the bird and take the little heart.
Take the grey key in B7 using a blue key.
Go back to B9 buy, fight the boss, and win.
End of Area 1. No sleep, only using 1 bought upgrade.