Generally speaking, First Edition Pokmon Cards are worth more than the later print runs
Despite that, most of the most expensive creatures in my cube do have abilities when they enter the battlefield or when you cast them while creatures like Etali are better here, theyre still very slow, you have to wait for an entire turn cycle, which is a lot of game actions, so you often want your creatures to have a more immediate impact, which enters the battlefield abilities offer
Recommended build x2 Mega Altaria ex x1 Altaria x2 Swablu x2 Chingling x1 Jirachi x1 Sableye x1 Sabrina x2 Rocky Helmet x1 Cyrus x1 Mars x1 Red Card x1 Lisia x2 Poke Ball x2 Professors Research Mega Absol ex & Hydreigon deck Mega Absol ex shines thanks to its very high HP and the ability to disrupt the opponents setup, revealing their hard and discarding a Supporter card
Silverquill Influence is probably great for precon battles, and Quandrix Unlimited lets you cast big dumb hydras, which is always a blast
My guess is that this was a playtest name given to the card by the design team and development loved it so much that they decided to keep it
