So much HP
Aside Ditto's achile's heel of failing on the bench, Ditto is an effective wall against anything with high HP. You get higher HP with snowpoint temple, and usually as you bring Ditto out when it can copy, you are getting first strike. In order for your opponent to outdamage you, they really need to keep a powerhouse on the bench to bring out when Ditto is out. Ditto isn't going down in one hit, and for the times when warp point or a retreat to a low HP poké does get it in one attack, not only have you forced them to essentially disrupt themselves by wasting game effects and resources, but you have only lost a basic pokémon, not a basic+candy+stage2.
Low attack costs are the play
Reading discussion of Legends Awakened cards and the DP-on metagame, I think certain cards with low energy attacks are getting a lot of limelight. Main example being Kingdra. Against Kingdra, Roseanne (or telepass a roseanne) will fetch you everything you need to fully setup a "Kingdra" in the form of ditto. Other pokémon such as the pixies, froslass or random things such as a Mewtwo after using Giga Blast. Jirachi and Furret are very copyable and may well see play.
Ditto can do stuff even if you can't copy
Call energy is highly played, and with the new technical machine cards, give Ditto lots of options if they try and disrupt your copying. Evolving your bench, devolving the pokémon you have softened (although this clashes with snowpoint temple) amongst other things is a very useful thing for Ditto to do if you really are out of options otherwise.
A good timewaster
Posing a threat using very few resources, allows you to develop stronger pokémon on the bench. While they are using candies, searching pokémon to attack ditto with or to reduce its max HP, you can focus your effects on a stronger pokémon. If they don't send out the bug guns for Ditto to copy, you can take the initiative with the pokémon you were developping. And of course, when they use something to stop that attack, Ditto can march right in and copy/wall.
So techable
Literally every single deck benefits from Ditto for mirror games. E.g. a Kingdra deck could use Ditto as a mini-Kingdra while you focus resources on Claydol to respond to an early Kingdra. A Magnezone deck could move all the energies needed over to a just played Ditto and copy their attack, free retreating back and pulling the energy back when Ditto is no longer needed. In an AMU mirror, you could copy Supreme Blast 200 after they have done it to you, or are building it. If you did not yet have Azelf LvX out, Ditto is a suitable pokémon not to take weakness damage.
And by the way, Ditto can copy Garchomp's restore without even needing a single energy. Could a Garchomp player ever take the risk you might drop a Ditto and restore straight back at them? (And for even more LOLs Garchomp is weak to Ditto's type, but Ditto isn't). So basically, Ditto is an autowin versus Garchomp.
- 8/10