Bacillus forms an endospore within the mother cell, which then degrades to release the spore. This gives a haploid genome in the spore. Myxococcus spores (myxospores) form from a single cell, and are diploid. A diploid spore will germinate faster, as it does not need to replicate its DNA on the first division.
The challenges involved with forming endospores and myxospores mean it is challenging to study. This is due to the stochastic formation of spores, and the differences between individual spores.