Inferno has traditionally kept to himself, troubling other dragons and the wider world little (except those who seek to violate his privacy)
A combination of obscene rarity, stellar artwork, usefulness on the tabletop, and a connection to one of MTGs most famous cards have coalesced to drive its price way up
#2 Gotta be And These are, similarly to the OP's, two lands from the same set
And cards like Mangara, the DiplomatMangara, the Diplomat and Body of KnowledgeBody of Knowledge fill our hands when our opponents try to hurt us
Mise en place also ties this and other spreads together massively in each piece of art
Its decent insurance against targeted removal spells, but its weakness is when a board wipe is cast, theres nothing to move the counters to