In a deck with Entomb style effects for Gisela and creature tutors for Bruna, it may not be too far-fetched to combine them, but its still a lot of hoops to jump through
Its never a bad thing to have a place to spend excess mana every turn, and a personal (albeit conditional) Howling Mine in white is nothing to sneeze at, either
Simple, and with offspring, these grow the board to difficult to manage levels quickly
while these cards cant win the game themselves, they can fill up the graveyard and enable powerful synergies
If you lose, creatures with power 3 or greater are destroyed instead
In doing so, youll create a lot of tiny loops or interactions that are very difficult for the opponent to topple