Like most Magic: The Gathering cards, the value of Arcane Signet 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 (Secret Lair Drop)
For those that want the lengthier version of the story on how Vehicles came to be, here's a link to the article that talks about it
Simply choose a card type (creature, spell, enchantment, etc.), upload your artwork, and add your own custom text and abilities
When it's defeated, exile it, then cast it transformed.) When Invasion of Muraganda enters the battlefield, put a +1/+1 counter on target creature you control
From here we can add lands to match these percentages
There's not much more to say here than I think this card is a nice way for Control to snag an early engine card from these decks, and then have room to Stock Up or Consult the Star Charts on the following turn