Cheapest this game has ever been. Lots of other Vita games on sale for lowest price ever:
Muramasa Rebirth $5.95 - https://store.playstation.com/en-au/product/EP1024-PCSB00404…
Hyperdimension Neptunia ReBirth1 $10.45 - https://store.playstation.com/en-au/product/EP0031-PCSB00579…
Zero Escape: Zero Time Dilemma $14.95 - https://store.playstation.com/en-au/product/EP1024-PCSB00942…
Ys: Memories of Celceta $11.95 - https://store.playstation.com/en-au/product/EP1063-PCSB00497…
SteinsGate $7.55 - https://store.playstation.com/en-au/product/EP4293-PCSB00724…
EDIT - just realised this list barely scratches the surface. Heaps of Vita and PSP games on big sale. Seems to be a JRPG or Japan theme
basically my whole wish list is on sale RIP