How exactly does an assassin work? I ask primarily out of curiosity.
The assassin has a bit more bookkeeping than necessary, I think. They're good killers, but since their main uses are being hired for assassinations and spying, they are almost always better used as NPCs. Also, they are always evil. Hanging around a paladin probably wouldn't work.
Still, here's a possible Assassin that can be made with the stats:
Human Assassin, (?) Evil
First Level
Strength 14
Intelligence 13
Wisdom 16
Dexterity 14
Constitution 12
Charisma 13
AC 7 HP 6
Saving Throws:
Paralysis, poison, death magic: 13
Petrification, Polymorph: 12
Rod, Staff, Wand: 14
Breath Weapon: 16
Spell: 15
Poison Use
Backstab x2 damage (+4 to hit if also surprising)
Assassination possible on surprise (see assassination table)
Disguise (2% chance of being recognized per day)
Spying (see DMG for details)
Weapon Proficiencies: Dagger, Bastard Sword, Heavy Crossbow.
Languages: Common, (?) Evil, Thieves' Cant, (can learn 3 more)
Equipment: Leather Armor, Small Wooden Shield, Bastard Sword, Heavy Crossbow, 20 Quarrels, Dagger, Cloak
Money: 14 gp, 15 sp (
Money (2d6=7) - 70)
Age (20+1d4=21) 21
(Height and Weight depend on gender)
Secondary Skills:
1d100=30 Animal Husbandry
Psionics:
1d100=41 No psionics.
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Here's a simple Elf Fighter I can make with the stats.
Elf Fighter, (?)
First Level
Strength 13
Intelligence 13
Wisdom 15
Dexterity 15
Constitution 11
Charisma 13
AC 2 HP 10
Saving Throws:
Paralysis, poison, death magic: 14
Petrification, Polymorph: 15
Rod, Staff, Wand: 16
Breath Weapon: 17
Spell: 17
90% resistance to sleep and charm
+1 to hit with bows, short swords, long swords
60' Infravision
Notice secret/concealed doors 1/6
Find secret doors 2/6
Find concealed doors 3/6
Surprise 4/6 when not in metal armor and with only other elves or halflings
Weapon Proficiencies: Short Bow, Long Sword, Short Sword, Club.
Languages: Common, (?), Elf, Gnome, Halfling, Goblin, Hobgoblin, Orc, Gnoll.
Equipment: Short Bow, Long Sword, Short Sword, Splint Mail, Normal Shield, Small Helmet
Money: 22 gp
Money (5d4=16) - 160)
Age (130+5d6=142) 142
(Height and weight based on gender)
Secondary Skills:
1d100=39 Limner/Painter
Elves do not have psionics.
Note that I'm giving only bare-bones equipment; feel free to fill in later.