RE: Thundurus / Deoxys / Kyurem PLS-on
IMO XY brought a lot to the tables for Plasma. Gaining Muscle band,it allowed a Lugia with 3 Deoxys and MB to OHKO a plethora of highly played EXs.However, with the increase in play of Yveltal/Garbodor,arguably the BDIF with the most Nationals top cuts so far,Raichu is popping up everywhere,due to it's splashable attack cost and nifty free retreat.With Raichu being a hard counter to Yveltal, Lugia gets hard countered aswell,as you may have expected.With just 4 benched Pokémon and a MB,raichu OHKOs either of the beefy birds.
After XY and into the NXD-FLF meta game, Lugia still sees play in the decks of some of the best players around.Be it Speed Lugia,turbo,or 'Yeti'(with snorlax and Lugia) , Raichu hasn't stopped it from wrecking EXS, ending the game in 2 turns is just too good.One of my good friends in the game,and fellow UK senior.Demetri Eaton played 'Yeti' and went on to win the UK national Championships.(I lost my last game to deny me of my worlds invite :'( ).
However, ever since the release of Plasma Freeze, TDK(Thundurus,Deoxys,Kyurem) has consistently been winning and finding itself at the top tables of loads of tournaments, for over a year.Kyurem , the decks focus can swing for 30 damage and a 30 snipe for 2 energy( W and C). This is very similar to Landorus EX but, Kyurem , being a team plasma Pokémon gets a lot of boost.Potentially hitting a 100/30 split with 4 Deoxys and a silver bangle,added to the fact that back then you could attack turn 1, it was just too good not to run in ANY Plasma decks.
Of course, it had it's counters, namely Cobalion-EX and Cobalion NVI, but, it was just supreme over Lugia until the release of XY.
Pros of Lugia:
Can be powered up t1
Can consistently KO pokemon for 2/3 prizes per turn
Win the game on the 2nd/3rd turn
2 retreat cost. Free retreat with a Glaceon(although I wouldn't recommend it)
Fighting resistance
180 HP
Cons of Lugia :
Gets KOd by raichu
Is an ex
Takes 4 energy to attack
Rekt by Yveltal(wrecks it in return,however)
More dependent on Deoxys than Kyurem
Pros of Kyurem:
Non ex
Steel weakness(barely used type)
Hits for 3 energy,not 4
OHKO potential
Snipe damage
Can set up KOs for Deoxys/Thundurus
Type advantage over Landorus,Delphox,others
Cons of Kyurem:
Doesn't take 3 prizes on exs like Lugia does
50 less hp than Lugia
Requires coloured energy
Now, although it seems Lugia is better on paper, I believe there's more to Kyurem than what people think
Overall I believe the 2 are equal in playability, as both have their pros / cons and can consistently do better than other decks.