Greetingz:
1st question: Specific locations. As u should know , there are 5 total glyphs, marked from I to V ( roman number ).
1st glyph: act1, Tamoe Highland -> The Pit lvl 2. Kill the superunique boss on there ( its one of those ravenspitting-trees )
2nd glyph:act2 , Rocky Waste -> go through stony tomb, u will encounter a superunique boss, a gloam, or something like that....
3rd glyph: act2, collapsed escape tunnel, which entrance is in the pallace cellar lvl 3, in the very north. Get lvl 2, and u will fight a superunique boss-worm
4th glyph: act3 , flayer jungle, swampy pit ( the other dungeon appart of Flayer Dung ). go lvl 3, and fight a super unique shaman boss.
note that this guy will drop two glyphs due to his reborn as a superunique fetish ^^!
5th glyph: act3, fortress of the Zakarum. Go to the very center and encounter a superunique LicH Boss ( easily identificable cause of his redemption aura ).
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2nd question: No, they will always drop, once per kill ( perhaps twice if you hork
) . You can get as glyphs as u want and/or need.and merry Xmaz
Laura♥