Only cards from EX Hidden Legends, EX FireRed and LeafGreen, EX Team Rocket Returns, and EX Deoxys are allowed. However, Energy from previous sets and Basic Fossil Cards are allowed (such as Mysterious Fossil and Root Fossil).
x3 Horsea (TRR)-Water Plant works great with Ludicolo, getting me Energy back to use with Healing Steps. Swift is a solid two for 30 that ignores resistance, Pokemon Powers/Bodies and other such things. Needed for evolution.
x2 Seadra (TRR)-Needed for evolution.
x1 Kingdra (TRR)-No weakness and 120 HP means that this card is hard to take down. Especially when they can't attack due to al their energy being discarded by Hyper Whirlpool. Aqua Sonic is a solid three for 50 that isn't affected by resistance.
x3 Lotad (Surprise) (Deoxys)-Surprise is a solid one for 10 that puts a card in my opponent's hand back in their deck. Needed for evoultion.
x2 Lombre (Blot) (Deoxys)-Natural Cure keeps Lombre protected from Special Conditions. Blot is a two for 20 that heals Lombre by two damage counters.
x1 Ludicolo (Healing Steps) (Deoxys)-Swing Dance lets me draw a card each turn. Healing Steps is a one for 30 that keeps Ludicolo healthy. Circular Steps can end up doing a lot of damage late in the game.
x3 Shellder (FR&LG)-Needed for evolution.
x2 Cloyster (FR&LG)-Exoskeleton reduces damage taken by 20, which makes Cloyster hard to take down. Double Bubble has a good chance to paralyze. Sheel Attack is a decent three for 50.
x2 Seel (FR&LG)-It can 30 damage for one energy. Needed for evolution.
x1 Dewgong (FR&LG)-Useful to take down Pokemon ex cards as it can't take damage from them. Cold Breath is a decent one for 10 that puts the foe to sleep and Dewgong can do an alright 40 damage for three energy.
x2 Qwilfish (TRR)-A 60 HP basic. When it takes damage, it deals back an infinite amount of damage back. With heads Stun Poison is decent, paralyzing and poisoning.
x4 Steven's Advice (HL)-Drawing.
x4 Pokemon Retriever (TRR)-Gets back cards discarded by Ludicolo.
x4 Energy Charge (Deoxys)-Gets back energies discarded by Ludicolo.
x2 VS Seeker (FR&LG)-Gets me back my Steven's Advice cards.
x1 Island Cave (HL)-Keeps my Pokemon safe from Special Conditions and gets rid of other stadium cards my opponent has.
x23 Water Energy-Needed.
My opponent stands no chance. Kingdra keeps them unable to attack. Ludicolo is able to heal itself from damage. Cloyster and Dewgong provide some nice Stage 1 bulk, Dewgong not being damaged by Pokemon ex and Cloyster preventing 20 damage. The basics also support this deck well, Horsea with Ludicolo and Qwilfish being bulky and high damaging.