If you loved Heavy Metal, try Asterix in Britain
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
What they share
Both films are directed by Pino Van Lamsweerde, and they sit in Adventure / Animation territory. If that's the register that drew you to Heavy Metal, the second film will land in a comparable space — through a different lens.
What Asterix in Britain is
The Asterix series had a good run of these. Our heroes venture to Britain to help a small village resist Roman conquest. They encounter local culinary horrors, and must secure a barrel of magic potion. It's probably one of the Asterixes.

