Lets hop aboard our airship and go collect some crystals
This can be compensated for with creature and utility lands to some extent but it will hurt your speed or your consistency to do so and is especially dangerous to do so heavily in a 15 land deck
One of the most broken effects ever printed
If we cast Sigarda on turn four, and attack on turn five, we have at minimum drawn our opening hand of seven cards, plus one for each turn
Any card that targets a creature and has a cantrip effect also becomes a mass card draw spell: cast a one mana Crimson Wisps or Expedite targeting Zada, and you'll draw a card for each creature you control
If you discover an adventurer card, split card, or modal double-faced card, you might be able to cast that card with either set of characteristics depending on the effect's discover value