I would say: Base Charizard (any variant) Base Blastoise (any variant) Base Venusaur (any variant) Base Pikachu (any variant) Base Machamp (any variant) (not that Machamp is popular, just seems that everyone had this card)
Your journey to Maximum Gold: El Dorado * begins this fall
I dont know what makes a Pokmon legendary or not legendary, so digging further into it I came across what I assume is an unofficial chart that tries to categorize the rare ones: This chart has three categories: Legendary Pokmon, Legendary Pokmon (Forbidden), and something thats tough to translate but is something like Mystical Pokmon or Mythical Pokmon

Decklist [COMMANDER] 1 Breya, Etherium Shaper [PLANESWALKERS] 1 Tezzeret, Betrayer of Flesh [CREATURES] 1 Chief Engineer 1 Disciple of the Vault 1 Eldrazi Displacer 1 Emry, Lurker of the Loch 1 Enthusiastic Mechanaut 1 Esper Sentinel 1 Etherium Sculptor 1 Foundry Inspector 1 Grand Architect 1 Ingenious Artillerist 1 Marionette Apprentice 1 Marionette Master 1 Ornithopter of Paradise 1 Pili-Pala 1 Reckless Fireweaver 1 Sharuum the Hegemon 1 Shimmer Dragon 1 Solemn Simulacrum 1 Thopter Assembly 1 Thought Monitor 1 Tribute Mage 1 Trinket Mage 1 Trophy Mage 1 Whirler Rogue [ARTIFACTS] 1 Arcane Signet 1 Ashnod's Altar 1 Cloud Key 1 Krark-Clan Ironworks 1 Midnight Clock 1 Nevinyrral's Disk 1 Nim Deathmantle 1 Panharmonicon 1 Skullclamp 1 Sol Ring 1 Sword of the Meek 1 Thopter Foundry 1 Time Sieve 1 Wayfarer's Bauble [INSTANTS] 1 Arcane Denial 1 Counterspell 1 Deadly Rollick 1 Despark 1 Fact or Fiction 1 Fracture 1 Frantic Search 1 Resculpt 1 Stoic Rebuttal 1 Swords to Plowshares 1 Thirst for Knowledge [SORCERIES] 1 Austere Command 1 Battle at the Bridge 1 Dance of the Manse 1 Feed the Swarm 1 One with the Machine 1 Open the Vaults 1 Painful Truths 1 Saheeli's Directive 1 Supreme Verdict 1 Thoughtcast 1 Trash for Treasure [ENCHANTMENTS] 1 Curse of Opulence 1 Ghostly Prison 1 Propaganda [LANDS] 1 Ancient Den 1 Command Tower 1 Contaminated Landscape 1 Drossforge Bridge 1 Exotic Orchard 1 Goldmire Bridge 1 Inkmoth Nexus 2 Island 1 Luxury Suite 1 Mistvault Bridge 1 Morphic Pool 2 Mountain 1 Myriad Landscape 1 Opal Palace 1 Path of Ancestry 1 Phyrexian Tower 2 Plains 1 Raffine's Tower 1 Razortide Bridge 1 Rogue's Passage 1 Rustvale Bridge 1 Seat of the Synod 1 Seething Landscape 1 Shattered Landscape 1 Silverbluff Bridge 2 Swamp 1 Tainted Field 1 Tainted Isle 1 Temple of the False God 1 Vault of Champions 1 Vault of Whispers As always all my decks come with at least 35+ lands 10/12 ramp 10+ draw 8+ removal 2+ board wipes 5+ protection And as always my decks are priced for quick sale at TCG low or better

(8/25/2017) If an activated ability of a card in exile with a cage counter on it references the card it's printed on by name, treat Mairsil's instance of that ability as though it referenced Mairsil by name instead
With Xolatoyac at the helm, you can go deep on counter and tap synergies, or maybe even find a way to turn that flood counter into a disruptive tool against your opponents