A very slow but reliable stratagy, using multiple boneyards, vultures, viruses, and plauges, you can become almost invincible.
At first, you need to build as many boneyards as possible, occasionally sending out viruses to attack and become fodder. Then, you wait until you have a plague and a vulture, and the enemy has at least on creature out (it is useful to have bone walls). Eventually, you should have a vulture that is at least a 3|2, and about a billion skeltons from the failed attempts (don't worry if your vulture never gets big enough, it really just needs to survive). Now, summon some viruses to attack your own skeltons. It will end up producing 1 skelton while killing your virus. It also make your vulture +2|+2. If your enemy has thunderstorm, even better, as it will kill the skeltons and MEGABOOST your vulture.
Optional Cards and final thoughtsEdit
have approx. 15 bone pillars
use the upgraded of all but virus, as it will kill your vultures