Algeron III (First Splinter)
From Trekipedia
Algeron III was devastated by isolytic subspace weapons during a battle between a Romulan bird-of-prey and a Graymel scourge vessel. The Graymel ship unleashed the subspace weaponry when it became clear that it was losing the battle, and the resulting fracture of space-time shredded the planet, killing the millions of inhabitants on the planet.[1]
