This would later be addressed, at least in temporary fashion, in Pokmon X/Y where Charizard gained the ability to Mega Evolve into the mighty Mega Charizard X, a Fire and Dragon-type with black scales and blue flame
In terms of judging card rarity in the Pokemon TCG, condition, age, scarcity, and print numbers are all considered when determining value
Basic Conjuration Bumi's Feast Lecture Containment Breach Cracked Earth Technique Cycle of Renewal Earthbending Lesson Elemental Teachings Fractal Summoning Germination Practicum Match the Odds Origin of Metalbending Pest Summoning Rockalanche Seismic Sense Shared Roots The Art of Tea True Ancestry
So why and how has this particular card, especially as it isnt even graded, fetched such a high price
The exact combo lines can be modular, but the core idea stays the same: get Lumra onto the battlefield, kill Lumra and/or sacrifice your Lands with the ETB on the stack, bring everything back, generate more resources than you spent, and repeat