Jesters Cap and Mask was pure control, not just for Blue but, for any color deck
9 Urza, Lord High Artificer Blue mana is all about wizards and artifice, and Urza, Lord High Artificer is the ultimate blue creature in that regard
UR Ultra Rare Gaiarmor Dragonshell X EARTH Level 6 [ DragonSynchroEffect ] ATK 2000 DEF 1300 1 Tuner + 1+ non-Tuner monsters You can Tribute this card, then target 3 other Synchro Monsters in your GY
The HR Rainbow (PLANETA Mochizuki, 34,800) uses the standard VMAX template with rainbow/gold foiling the traditional high-rarity treatment
Summary Foundations cards are becoming staples in many formats, including Standard until 2029, making them a worthwhile investment