Most Melodic Opeth Song.

I have no understanding of how The Leper Affinity could be their most melodic song....wouldn't more of the harmonic stuff from Orchid or Morningrise be more melodic? I'm going with Night and Silent Water, In Mist She Was Standing, or Forest of October.

I think I don't know how melody is defined in music.I am not a pro anyway..

What I am trying to say is some songs are much more riff-oriented ( Heir Apparent,Hex Omega,Beneath the Mire) while some have less riffs and much more continuously played notes.( The Leper Affinity falls in this category,also Face of Melinda or Ending Credits)

I think my perception of melody is a string of notes played continuously ( like solos) and riffs are short but ass-kicking ( the beginning of Master's Apprentices.)

If someone with musical knowledge can clarify this I would be happy.
 
In music, a melody (from Greek μελῳδία - melōidía, "singing, chanting"[1]), also tune, voice, or line, is a series of linear events or a succession, not a simultaneity as in a chord (see harmony). However, this succession must contain change of some kind and be perceived as a single entity (possibly Gestalt) to be called a melody. Most specifically this includes patterns of changing pitches and durations, while most generally it includes any interacting patterns of changing events or quality. "Melody is said to result where there are interacting patterns of changing events occurring in time."[2]

Change is necessary for events "to be understood as related or unrelated." Melodies often consist of one or more musical phrases, motifs, and are usually repeated throughout a song or piece in various forms. Melodies may also be described by their melodic motion or the pitches or the intervals between pitches (predominantly conjuct or disjunct or with further restrictions), pitch range, tension and release, continuity and coherence, cadence, and shape. "Many extant explanations [of melody] confine us [sic] to specific stylistic models, and they are too exclusive."[2]

To clear up any defenitions.
 
Something off the first two albums, obviously, all other suggestions will be auto-fail. The first 2 albums are very clearly all Gothenburg-style twin guitar melody driven; while the rest are more chorus-driven (which is why they're better)