With so many sets in Pioneer, the chance that the energy core is just the best way to build decks to such an oppressive extent is much less likely than it was in Standard because ultimately there are still only two sets that contain these energy cards
(Im at work, so Ill update the topic to have all the cards text written plainly on my next break or when I leave 4 the day.) So basically, the idea is that each Omega Monarch can serve as a Boss monster for any given Monarch or mono-Attribute deck, with accompanying Field Spells to heighten that angle
I know that there are some seriously evil lands in Legacy and Modern (Dark Depths, Wasteland, Valakut, the Molten Pinnacle, Celestial Colonnade, Eldrazi Temple and, of course, Tron), but youre losing card advantage while also giving your opponent a free rainbow land
Its more of a show-off card than a plug-and-play Pokemon for your decks