The Dark Star War. Codex Regius, #3

The war with the Shaitans continues, and Lieutenant Commander Shawn 'Calvin' Hobbs has stayed behind to help the reptilian Ssselipsssiss race fight the Shaitans while his ship, the TSS Vella Gulf, has gone for aid. Formerly enemies, Calvin now finds himself supporting the Ssselipsssiss in their war against the Shaitans in a "must-win" situation. If the Ssselipsssiss fall, Terra is next!Able to operate in two universes and armed with unavoidable time-based weapons, the Shaitans have proven unstoppable.
Although Calvin has experience fighting the Shaitans, the Ssselipsssiss are down to their last three planets, and Calvin's assistance may very well be too little, too late. The only ship with any success against the Shaitans is the Vella Gulf, which can jump to the Shaitans' universe and fight them on their own turf. But time is short; will the crew of the Vella Gulf be able to find the mysterious "Dark Star" system of the Shaitans and stop them before they destroy Terra?Faced with an implacable foe, the Terrans have been forced into an alliance where the enemy of their enemy might be their friend.or might not.
The crew of the Vella Gulf will have to choose their allies wisely as the stakes are the highest possible-only one race will survive the Dark Star War!