Like most Pokmon cards, the value of Heatran 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 (SM Black Star Promos)
Melira, the Living Cure Melira, the Living Cure will be a very helpful creature in All Will Be One Limited thanks to the prevalence of toxic creatures
I nicknamed the two in that art Luya and Jaha after the programming languages LUA and Java because they were robots
Build up your board with creatures and planeswalkers, steadily gaining advantage and controlling the game
A Relic Token Pack from the Relentless Collection
If they are both in your graveyard, you can activate Haunted Dead's activated ability to trigger Prized Amalgam and cheat it into play