This deck leans into this strategy, offering ways to sacrifice creatures to draw cards, card advantage and life drain for going wide, and X-spells that generate plenty of token creatures
3 Prismatic Secret Rares
However, mana for an activated ability is pretty steep, so running cards that reduce this cost like Zirda, the Dawnwaker and Heartstone are beneficial
If a blocker is in play, Kaido effectively shuts it down, letting us attack the opponents Leader without worrying about our attack being blocked
Relay Soul sounds like a problematic and powerful combination when it can be drawn into, along with you being able to take down the monster, along with your opponent having the incredibly easy scenario of having a monster to Summon, so assuming rulings don't disable it completely (which they could due to the unexplored nature of these effects), I still think it feels wrong to favor it over this