While in the Desolate Sands during Act II, when you encounter the Nine Toads enemy, notice that it is described as the "terror of the Borderlands". It is also accompanied by nine toads, which is a reference to the "Nine Toes" Boss in Borderlands.
When you enter an area that gives you a life potion or chest, make sure to collect them. Then, leave the game and resume it. The place where you clicked on to get the previous potion will give you another potion every time. Note: There may not be always a chest; if this happens, leave the game and resume it. Most of the time another chest will appear, and the treasure will vary from an item to gold, or both.
If your chosen character class is a Monk, use the following skill setup to become very effective against almost all enemies. To start with, set the Primary Attack to Way of the Hundred Fists and attach the Rune Hands of Lightning. For the Secondary Attack, choose Wave of Light with the Explosive Light rune attached to it. For Skill Button 1, choose Blinding Flash with Blinding Echo as the attached rune. For Skill Button 2, choose Exploding Palm with Strong Spirit as the attached rune. There are various options for Skill Button 3. If facing a Boss, choose Mystic Ally with your choice of rune. In normal game play, choose Seven Sided Strike with the Several Sided Strike rune attached to it. For Skill Button 4, choose Mantra of Retribution with the Retaliation rune attached to it. For Passive Skills, choose Transcendence, Seize the Initiative, and Pacifism. This setup will allow you to handle any situation that is thrown at you. Note: If surrounded, use the secondary attack. It will clear the area and heal you at the same time. Blinding Flash is also very useful.
 Open the "Sound" options and uncheck the "Show Quest Dialog in Chat" option in the bottom right corner.
The item required to unlock the secret cow level is the Staff of Herding. To craft it, you must obtain its recipe, five rare items, and 150,000 gold under the Normal difficulty setting. The recipe appears in Act 4 under the Normal difficulty setting, from Izual. The items required for the recipe are as follows. Each of the items bind on acquire and cannot be sold or traded.
Craft the Staff of Herding and find a dead cow in Old Tristram, west of the road. Use the Staff of Herding to open a portal into Whimsyshire. To reach higher level versions of the secret area, you must make special new versions for each difficulty setting.