Animorphs

Animorphs.

Cool friends fighting aliens...more accurately, the pariah of a fascist civilization, minutes before being eaten alive in front of said "ccol friends" persuades and then bioengineers Earth child soldiers to facilitate an end to an ill-conceived and failing war now reduced to unilaterally exterminating a parasitic, physically disabled species, itself undergoing a violent civil rights movement on their own planet based on their self-recognized flaws, struggling to realize its place in a universe where godlike beings exist and decide not to offer a simple, viable remedy to said parasitism(rules of the god game), because the pariah's alternative to genocide is to allow the parasites to overwhelm all vulnerable species in the known universe, to which the earth child soldiers respond, "we'll help you resist, but genocide sounds wrong" but then, after being physically and emotionally tortured a dozen times, shot and repeatedly disemboweled and having their limbs cut or bitten off by the parasitic species, genocide begins to make a lot of sense to the child soldiers and they begin making choices that end their lives as they know them.

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