While the general consensus is that it's fine as it is because mana production of this sort is a green mechanic, some people are still sold on the fact that it makes mana based on the number of enchantments out on your side, which has been done by Serra's Sanctum back in the Urza's Saga expansion
After Melding to put Urza, Planeswalker on the board, using its +2 ability once will let you loop Ghostly Flicker endlessly
Japan usually gets the newest mechanics and designs first, meaning Japanese collectors always have a head start
As one of Magic: The Gatherings most popular and powerful planeswalkers, Jace Beleren has seen plenty of iterations and planeswalker designs over the years
Ninja Treatment There are 22 Ninja creatures in Kamigawa: Neon Dynasty , plus the ninja planeswalker Kaito Shizuki
Its also cool that unlike Champion(s) of the Parish/Perished, the Colossus doesnt mind if you draw it later on in the game after casting your other Zombies