The Platinum Slaking was largely ignored prior to its release, and for good reason. It cannot attack if it attacked last turn! This plus its Retreat Cost of 4 made it largely unplayable and incredibly slow. However, Dialga G LV.X changes all of that.
Dialga G LV.X gets rid of Slaking’s Poké-Body. Now, it can attack every turn for 150 damage! This makes it a much much more efficient card. However, damage done to Slaking after he uses his attack is increased by 50. This severely weakens him. However, a simple Unown G will eliminate that problem, because Unown G will “prevent all effects of ATTACKS” done to Slaking, not necessarily only the opponent’s attacks. Slaking is now dealing 150 for any 4 Energies every turn with no downside!
However, 4 Energies is still very many, especially in such a fast format. However, with the release of the next set, we will be blessed with Double Colorlesss Energy. This makes Slaking much, much faster, with the possibility of powering him up in one turn! Let’s say you have Dialga G LV.X and Leafeon LV.X on the Bench. Play Broken Time-Space, play Slakoth-Vigoroth-Slaking, give it Unown G, attach 2 Double Colorless Energies with Energy Forcing, and attack for 150 every turn with no downsides. This is why I believe Slaking will emerge in the metagame after the release of the next set.
Please comment if you have anything to say!