What!? No 360 degree vision!?
j/k, but I do remember a scene where a monster attempted to catch the Guyver unaware from behind. One of the metallic lobes on the top of Guyvers head moved, as if it were an eye. Guyver responded as if having seen said critter and, well... you know the rest.
Also, for some reason I keep thinking that the Acolyte of the Skin would be more appropriate (the skin thing, and Guyvers extradimesional nature may qualify it as a type of outsider).
Anyway, I found the AotS Epic progression at WotC web site. I figure that the spell-like abilities can be replaced with something more appropriate. Just a thought though...
Hope it helps.
Acolyte of the Skin (Outsider)
By 10th level, the acolyte of the skin is permanently bonded to his fiendish epidermis, transforming his type to outsider. He has a +2 natural armor bonus, a +2 modifier to Dexterity and Constitution, cold and fire resistance 20, 120-ft. darkvision, and a variety of supernatural and spell-like abilities related to his fiendish nature. However, other than the character's spells-per-day progression and bonus feats, no clear pattern of ability gain exists.
Therefore, to continue the acolyte's "journey" into fiendishness, we must extrapolate additional class features for the character. We can do this by examining the half-fiend template, as well as the common powers possessed by demons and devils.
A half-fiend has the following ability modifiers: Str +4, Dex +4, Con +2, Int +4, and Cha +2, which substantially exceeds what the acolyte gains. Occasional ability modifiers might be a good place to start for class features.
In addition, the half-fiend has a list of a dozen potential spell-like abilities, only two of which (poison and summon fiend) the acolyte shares in any form, as well as poison immunity and acid and electricity resistance 20. Here, then, are other good options for the epic character.
Looking at demons and devils, we find that telepathic communication is a common ability. They tend to have high Strength and Constitution, and many are highly intelligent, wise, or charismatic (or all three).
From these elements we put together a reasonable epic class progression for the acolyte of the skin.
Hit Die: d4.
Skill Points at Each Additional Level: 2 + Int modifier.
Spells: The epic acolyte's caster level increases by 1 every even-numbered level gained above 10th. In addition, at every even-numbered level, the epic acolyte of the skin gains new spells per day as if he had also gained a level in whatever spellcasting class he belonged to before he added the prestige class, up to the number of spells per day possessed by a 20th-level character of that class.
Physical Power (Ex): At 11th level, and every 10 levels thereafter, the epic acolyte of the skin gains a permanent +2 bonus to Strength or Constitution (character's choice).
Poison Immunity (Ex): The epic acolyte of the skin becomes immune to poison at 11th level.
Fiendish Heritage (Sp): At 13th level, and every 4 levels thereafter (17th, 21st, and so on), the acolyte of the skin gains one daily use of each of the following powers: desecrate, unholy blight, and blasphemy. Use the character's acolyte of the skin level as the caster level.
Acid Resistant (Ex): At 14th level, the fiendish skin grants acid resistance 20.
Improved Symbiosis: At 15th level, and every 5 levels thereafter, the enhancement bonus needed to bypass the damage reduction of the epic acolyte of the skin increases by +1 (to DR 20/+2 at 15th level, DR 20/+3 at 20th level, and so forth).
Mental Power (Ex): At 16th level, and every 10 levels thereafter, the epic acolyte of the skin gains a permanent +2 bonus to Intelligence or Charisma (character's choice).
Electricity Resistant (Ex): At 18th level, the fiendish skin grants electricity resistance 20.
Telepathy (Su): A 19th-level acolyte of the skin can communicate telepathically with any creature within 100 feet that has a language.
Bonus Feats: The epic acolyte of the skin gains a bonus feat (selected from the list of epic acolyte of the skin feats) every 4 levels after 8th.
Epic Acolyte of the Skin Bonus Feat List: Armor Skin, Energy Resistance, Epic Spell Penetration, Epic Toughness, Extended Life Span, Improved Combat Casting, Improved Darkvision, Improved Spell Capacity, Spell Knowledge.
Acolyte
Level
Special
11 Physical power, poison immunity
12 Bonus feat
13 Fiendish heritage (1/day)
14 Acid resistant
15 Improved symbiosis
16 Bonus feat, mental power
17 Fiendish heritage (2/day)
18 Electricity resistant
19 Telepathy
20 Bonus feat, improved symbiosis