You cannot Special Summon from the Extra Deck, except Fusion Monsters, the turn you activate either of this card's effects
Deckbuilding implication: you need mana consistency , defensive interaction , and finishers that end games instead of generate value. Good questions: Can I reliably cast my top end

Mime) #38Uncommon $50.36 Ditto - 039/113 (Pikachu) #39Uncommon $83.02 Ditto - 040/113 (Squirtle) #40Uncommon $76.23 Dragonair - 41/113 (Delta Species) #41Uncommon $7.72 Dragonair - 42/113 (Delta Species) #42Uncommon $11.11 Golbat #43Uncommon $1.02 Hariyama #44Uncommon $1.76 Illumise #45Uncommon $1.62 Kakuna #46Uncommon $2.26 Kirlia #47Uncommon $2.51 Magneton #48Uncommon $1.34 Metang (Delta Species) #49Uncommon $4.39 Persian #50Uncommon $3.28 Pupitar (Delta Species) #51Uncommon $2.52 Rapidash #52Uncommon $1.99 Shelgon - 053/113 (Delta Species) #53Uncommon $1.50 Shelgon - 054/113 (Delta Species) #54Uncommon $2.73 Skarmory #55Uncommon $2.67 Volbeat #56Uncommon $1.07 Bagon - 057/113 (Delta Species) #57Common $0.57 Bagon - 058/113 (Delta Species) #58Common $1.04 Beldum (Delta Species) #59Common $1.03 Cubone #60Common $6.10 Groudon Star #111Ultra Rare $1010.00 Metagross Star #113Ultra Rare $951.99 Umbreon (Delta Species) #17Holo Rare $457.36 Mewtwo (Delta Species) #12Holo Rare $329.99 Dragonite (Delta Species) #3Holo Rare $269.95 Vaporeon ex #110Ultra Rare $254.33 Rayquaza (Delta Species) #13Holo Rare $220.00 Espeon (Delta Species) #4Holo Rare $212.50 Flareon ex #108Ultra Rare $211.62 Jolteon ex #109Ultra Rare $209.95

This allows you to slow down a game until it benefits you to play more than one card a turn, or you can finish a game with direct damage
We can pump our commander all we want, but if we can't hit someone for damage, what do we do
Others even help you fill up your inkwell so you have more ink to use for bigger plays