Kaza fills one of Izzet's weaknesses by essentially mana ramping for each of the most important pieces in your deck
It makes sense why this card is banned Modern and Legacy and restricted in Vintage
Bloodbraid Challenger is close enough to Bloodbraid Elf to not stain the name, and at a mana value one greater, with the ability to escape, the Challenger hits differently and I'm OK with that
Shifts in collector preferences, changes in the popularity of certain sets, or the release of new cards can all impact the desirability of older ones
And those valuable cards are the topic of today's article
Overall, if you pick good themes (popular character, limited availability, strong artwork) and hold through time, Japanese cards often offer compelling value upside