How angels were created, daily, for the purpose of singing the praises of God... Or via the utterances of God. Plus, R. Akiva's foray into aggadic interpretation and the double rebuke he receives for his efforts. Also, how R. Yochanan ben Zakkai taught, or didn't, the Ma'aseh Merkavah to R. Elazar ben Arakh. And what happens to R. Elazar ben Arakh when he delves in on his own, including the creation of angel(s), and the connection of his enterprise to Avraham Avinu. Plus, the rainbow in the cloud when R. Yehoshua and others were learning Ma'aseh Merkavah.