Early sets, OP-01 through OP-05, spent that initial window as Japanese-only products, and the first-to-market scarcity premium has proved durable on specific cards from those sets
For players who want the Garchomp ex in their deck without the SAR premium, this is the practical choice
You can also find resale options at some local card game stores or even TCG events, so its worth seeing what options are available to you in your immediate area
Appa, Steadfast Guardian gives you some wrath insurance, blink synergy, and outs to an easy one-two infinite combo with Aang, Airbending Master
The only black bordered 13 Mana Spell - Emrakul, the Promised End This card makes me think of the Eldritch Moon Pro Tour
Time Sieve Since you are making so many artifact tokens, Time Sieve is a phenomenal include as a way to easily generate extra turns