Like most Pokmon cards, the value of Koga's Golbat depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Gym Challenge)
That makes it incompatible with a black and blue commander
The difference between Bitter Reunion and other sources of haste is you get something else, too, and that something else is card advantage
What were your favorite sights from the Grand Prix
Pull rate from Rare Packs: 2.56% The estimated pull rate for Magikarp (Wisdom of Sea and Sky) from a Rare Pack is approximately 2.56%, meaning you might need to open around 40 Rare Packs to obtain it
For Murders at Karlov Manor onwards, The List will be pared down to just 40 cards per set