If I use Hook to look at the top card of my deck and see an Undertitan, do I get to float 2 energy?

Ruling: No, you do not get the 2 energy from Undertitan when using Hook. Hook only lets you look at cards, not reveal them, and Undertitan's ability requires the card to be revealed from the top of your deck.

Nuances:

• Look and Reveal are different game actions - looking at a card does not count as revealing it
• Cards like Nocturne work with effects like Stacked Deck because Nocturne's text specifically says "As you look at or reveal me from the top of your deck" (covering both cases)