Don't pick with your heart. Pick with your brain.
The Verdict: Pick Totodile. Intimidate pivoting is a Nuzlocke lifesaver.
Do not go in blind. Download the "Sacred Gold Documentation" (usually a PDF or .txt file) that comes with the hack. It details:
Many gym leaders run weather teams (Pryce = Hail, Jasmine = Sandstorm). Bring your own weather to override theirs. Rain Dance is your friend against Pryce’s Blizzard spamming.