{#each groups as [number, encounters] (number)}
{@const p = encounters[0]}
{@const levels = encounters
.flatMap((e) => [e.minLevel, e.maxLevel])
.filter((n): n is number => n !== null)}
{@const min = levels.length ? Math.min(...levels) : null}
{@const max = levels.length ? Math.max(...levels) : null}
{/each}