The power of the cards within a set is one of the most common ways to drive demand, either through desirable reprints or entirely new cards
On that note, it is very worth it to consolidate your level ones into Dullahan, even when it requires normal summoning, especially beside a Jiangshi since youll have 3 Ghostricks on board before XYZ summoning allowing you to search a level 3
Store upright
add 1 Level 4 or higher "Vampire" monster from your Deck to your hand, and if you do, send 1 Level 2 or lower "Vampire" monster from your Deck to the GY
If they are the same type (Fusion, Synchro, Xyz, or Link), send your opponent's card to the GY, and if you do, Special Summon your card, then, if the cards have the same original Type and Attribute, your opponent loses LP equal to their revealed card's ATK
In the Japanese version, Mizar implies that sometimes "Tachyon Dragon" would free itself and he would need to reseal it, getting exhausted every time