They can also have an extra deck that allows them to change out cards in their main deck
Do you understand, this is despair
Since the card only specifies it can Special summon a Level 1 Fire monster rather than specifically a Snake-Eye monster, it can be used to bring out Hydrant directly from the deck as another outlet for starting your Rescue-ACE combos
Some cards can only be obtained in the game by using a password: Password from Weekly Shnen Jump 2015, Issue 3: "Hi-Speedroid Kendama" Password from V Jump February 2015: "Ultimaya Tzolkin" Password from Jump Festa 2015: "Holactie the Creator of Light" Password from Tag Force Special Strategy Guide : "Harpie Harpist", "Number 95: Galaxy-Eyes Dark Matter Dragon" and "Masked HERO Anki"
It is cool idea for decks that control their top decks, and have a bit of sacky Graveyard reliance (Sylan, as you mentioned, and Back Jack related decks usually), but as far as anything else
You can only use each effect of "Seventh Ascension" once per turn