Specifically: Enduring Courage Enduring Curiosity Enduring Tenacity Enduring Innocence Enduring Vitality Overlord of the Balemurk Overlord of the Boilerbilges Overlord of the Floodpits Overlord of the Hauntwoods Overlord of the Mistmoors The Japanese Showcase versions also come in non-fracture foil editions, which are quite a bit cheaper, but these Japanese Showcase versions are only available in foil, either fracture or regular
When a demon equals play, it deals damage equal to its power to any target - like Scourge of Valkas, only for demon tribal instead of dragons
Finding whatever piece is missing of a Devoted Druid/Vizier of Remedies combo, tutoring up the Glen Elendra Archmage that will lock your opponent out of the game, or just turning a Kitchen Finks into a more valuable situational replacement these are scenarios that seem much more Modern plausible than surviving to the point where your Breaching Hippocamp finally gets to do something meaningful
The synergy between Ambers sustain and Rubys speed creates a deck that rewards proactive play
They're not Chandra's goggles
If your deck is very aggressive and looking to push through damage, that also ups the power of first strike since you will want to push for damage early in the game as much as possible and the late game isn't quite as what you're playing for