What is an example of irony in The Hunger Games?

Katniss steps in for her sister, Primrose, to save her from a certain death only to watch her little sister die in the capital because of a contraption her best friend, Dale, helped make to destroy the capital.

This, I found, was the most ironic and saddest part of the Hunger Games trilogy.

Peeta Mellark is named after bread

Cato is killed by the mutants which were in turn the tributes he murdered

Peeta Mellark camouflages himself by using the one skill Katniss made fun of him for in training. (cake frosting)

Sorry that's all I've got, :/