That scry is nice over time and I added a few cycling lands to my mana base to get free scries from, and it works on channel stuff as well
In my opinion, it could even change to discarding any kind of card and staying for either player's Spell/Trap activations, and it'd still be fine for the most part
None of the cards themselves are super interesting, though, effect-wise or artwork wise
Instead, these are part of the Stellar Sights bonus sheet, which means these cards can be found alongside many other lands in any type of booster pack but are not being added to any formats they aren't already a part of
After getting a fifth copy of a card, instead of the card itself, you'll get Credits, which will help you to craft more unique cards