Proliferate is the efficient answer
These planeswalker cards appear in foil and are part of each deck's 99
Chart shows the price of Dark Tyranitar [Cosmos Holo] #20 at the end of each month going back as long as we have tracked the item.
17) 1999 Pokemon Japanese Tropical Mega Battle Number 2 Trainer Sold in October, 2020 for $50,300 Held at the Hilton Hawaiian Village from 1999 to 2001, the Pokemon Tropical Mega Battle gave the best players from the United States, Canada, Latin America, and Europe the chance to test their skills against each other
While its ability to replace self is a definite bonus, having the repeatability of Penance or Hidden Retreat just stood out as a better option
But if you build it like that, you might miss out on the powerful blink deck that this can also become