Neon burning ($2{}^{20}\mathrm{Ne}⟶{}^{16}\mathrm{O}+{}^{24}\mathrm{Mg}$)

High-temperature photodisintegration of neon-20 releases an alpha particle and oxygen-16. Capture of that alpha particle by another neon-20 nucleus produces magnesium-24. The breakup consumes energy, but the combined reactions can release net energy. Other captures modify the ashes in a real network.