The 99 issues before this one:
36 – Warlord of Mars (35 issues + 1 Annual)
37 – Warlord of Mars: Dejah Thoris
12 – Dejah Thoris and the Green Men of Mars limited series
4 – Dejah Thoris and the White Apes of Mars mini-series
5 - Warlord of Mars: Fall of Barsoom mini-series
5 – Warriors of Mars mini-series
This issue is a variant of
Warlord of Mars (Dynamite Entertainment, 2010 series) #100 [Main Cover - Joseph Michael Linsner].
There exist further variants: