The cost cliff is the SIR Charizard ex #223, which at $104-130 raw accounts for 20-30% of what the full 406-card master set (197 base + 176 reverse holos + 33 secret rares) costs via singles today
Have you started looking into Pokemon TCGs newest set, Obsidian Flames
I did a bit of research, and I believe that right now, the top two decks in Standard (GB Delirium and UW Flash) are about as dominant as they have been over the past few years, but there isn't one deck (or card) that's dominating (or breaking) the format
When a permanent enters the battlefield it receives a timestamp
instead, they affected almost every chain roughly in proportion to its footprint
The card itself is reminiscent of Phyrexian Gargantua, which we know is a very powerful card