What to read after Ender's Game - Ultimate Collection?

Ender’s Game is a series of comic book adaptations of science fiction novels written by Orson Scott Card published by Marvel Comics that began in October 2008. However, some have been all new content, not released before in novel format. The series, like the novels they are based on, are set in a future where mankind is facing annihilation by an aggressive alien society, an insect-like race known colloquially as “Buggers” but more formally as “Formics”. The central character, Andrew “Ender” Wiggin, is one of the child soldiers trained at Battle School (and eventually Command School) to be the future leaders of the protection of Earth. The year is never specified, although the ages of the Wiggin children are specified to change throughout space, also carefully taking in the relativity of space and time.