He's talking about the EDHREC list. For reference:

Y'shtola, Night's Blessed- 53,694

The Ur-Dragon- 50,668

Edgar Markov- 50,595

Atraxa, Praetors' Voice- 44,420

I don't think the drop is as big as you may think. EDHREC culls older decks from the count, which helps newer decks. Additionally, Ur and Ed have been near the top (Ur occasionally above) near Atraxa for years.

The interesting part of the list to me, is not that Atraxa is 4th, but the relatively new Y'shtola, Night's Blessed is first.

DragonMaster420

The original legends rule didn't 'separate players.' As in, I play Jace Beleren. Then, opponent (or any player including yourself)) plays Jace Beleren (or any Planeswalker with Jace subtype like Jace Reawakened). This results in the original Jace being sacrificed which worked as bonus/free removal for opponents.

When they updated, they allowed different or separate players to have the same legendary which I 100% agree with. However, they also allowed the same player to have both Jace Beleren and Jace Reawakened (or any combo of different named Jaces).

I wish we we're limited to one named legend,as in only one Jace or one Chandra, etc. as the original rule worked.

He's referring to the old Legends rule but used a creature as an example.

E.g. The best way to kill an opposing legend was to play it's mirror because only one was allowed on the field.

It also applied to multiples of the same legend, such as only allowing one Jace planeswalker even with different names. Wish the updated rule would of just separated different players, because having 5+ Jaces on the field is weird.

I think Spark Double was the first (outside Mirror Box effects).

They've definitely become more common since War of the Spark. Too many? Probably?

Once something sticks or become popular/fun to play with, WOTC starts printing more of it. Spark Double is a fun card and can be outrageous. But he can also be a dead card since he has to target your creatures (a limitation Dragonmaster420 alluded to and something I've seen too many times with a The Prismatic Bridge  ^Flip commander).

I'm closer to your side of the fence DemonDragonJ, but probably more because I'm an old fogey and not because the clones are breaking the game/lore.