The cards in my collection often change in large quantities I have 4 to 6 easy to get beginner decks
The odds of catching your opponent on all nonbasics even in the non-Astrolabe games is basically zero, especially when they preemptively fetch their basics in anticipation of drawing Astrolabe later
Whether a part of control, aggro, tempo, or combo decks, Brainstorm was an absolutely defining force in Vintage until its eventual restriction, and to this day, is clearly way, way over the line for Legacy, except that it just gets a pass, because we want it
Other High-Power Creatures The first thing Id start looking for with a Ryu deck is high-power creatures that you want to attack with, and luckily, Boros has no shortage of goodies in that department
Creature - Goblin Rogue Mastery of the Unseen Whenever a permanent you control is turned face up, you gain 1 life for each creature you control