There are some combo decks where a combined lifegain tool, sac outlet and tutor is the dream card
Against slow and clunky midrange decks, ideally three or more colour ones you can expect the Sundering Titan to be pretty game endingly brutal
Sure, Kaervek's Torch can kill one creature or be sent to the dome for the win, Ray of Command would generate at minimum two-for-one card advantage every time it was cast
Bitterblossom + Skrelvs Hive + Dreadhorde Invasion Skrelv's Hive and Dreadhorde Invasion iterate on the template Bitterblossom established
You arent putting Whirler Virtuoso in the deck as a primary energy sink, but if your opponent passes turn in a spot where dumping everything into thopters will give you on-board lethal, youre free to do that
A big portion of the price of the Shivan Dragon above stems from the fact that it is a BGS-graded Alpha card