That’s not bad, but you’ll have the same possibility to draw an ogre and the same to draw a skeleton. At the other hand the D12 dices are also beautiful and it’s not a taboo to use more dices, no one will complain…
The difference is that if you want to make three quests for the weekend, for an undead campaign, and you don’t have time to draw tables and calculate the encounters. This tool will help you a lot. For example take a look to the picture bellow… I’ve put the monsters that I want to use and I change the difficulty trackers, and it’s done.
If the chaos wizards have one random chaos spell it is ok, but if the necromancer has all his spells you have to do changes. It is far more difficult than the 1 chaos and 4 skeletons, so try to use the text editor and put him last with the treasure of 100 gold coins. And press the “ReDraw” button.
But even if you don’t want to use this as a wandering monster table, you can use it as an index to design your map. For example you can place 12 rooms with each encounter of the matrix.
Also, you may have more minis, and you want to use them in your games. It is a nice way to add them by using this program. There is more than one reason to use it.