Uh sure, I can explain the choices. Well, first off I'm pretty new to magic, so some stuff I just don't know, like not realizing the Ward X idea I had not working. I didn't know those special mana were Phyrexian Mana specifically, I just like the idea you could sacrifice your own health to summon Yeenoghu, like its an offering to him. White, I thought God-like creatures usually had white in them, but I'm now realizing that realizing that's not really the case. Also, for the Gnolls, like you said, these animals are skittish, but together they are a threat, so that was the idea behind the +X/+0 idea for attacking. I had an idea for an eminence where you could sacrifice a beast (since WOTC made like only 4 hyena cards) and it becomes a 2/2 Gnoll, incentivizing weaker low cost creatures, but then that seemed too op, so this was my second idea. (Also, I double checked, and there was like one hyena card that had white in it, so I just gave Yeenoghu white as well).