Rivkin was a custom class from 2e, skills and powers + DMG rules.
His background was came up as a failed businessman, thug and do-anything for hire guy, to a paid killer. Always with an eye on finance and creating his own larger criminal organization. Converting this to 5e is no mean feat, but with the highly customizable options, completely doable.
Background: (using just the players handbook)
Guild Artisan (cast down/out of the guild for dabbling in forbidden secrets – ended up in the streets)
Proficiency: Insight, Persuasion;
Tools: poisoner’s kit
Business: Alchemist and apothecaries
Magic Using capability
Rivkin had a touch of magic powers – enough for him to know it when its being used and a few highly specialized pieces of magic that assisted him in his craft of tracking down and killing targets. These were all based on the tradition of the scholarly magic user of early DnD editions. His interest in magic was small and never progressed far.
Wizard 4th (4th because he had one more second level spell than normal rules for 3rd level (we used Int bonus)
HD: 4,4,4,4 = 16 +4 = 20
Arcane Tradition: Divination – This reflects the high level of long range planning and intelligence he specialized in
Proficiency: (as multiclass) None
Cantrips: Prestidigitation, Mage Hand, Message, Minor Illusion
1st level spells: Sunes Scar Ward (custom), Detect Magic, Charm Person, Comprehend Languages, Feather Fall, Fog Cloud, Protection from Evil/Good, Unseen Servant, Disguise Self
2nd level spells: Rope Trick, Arcane Lock, Locate Object, Detect Thoughts, Phantasmal Force
Rivkin was a light fighter, preferring weapons that could be concelaed, or using light weapons that made the best use of 2 handed fighting using dexterity. He was the equivalent of a 7th level fighter in the 2nd edition (beginning of extra attacks) rules. His early years were based on a lot of surprise attacks, and poison use. Based on equivalent power in 5e, that translates to the use of action Surge (Rivkin was really only good for a few rounds) but not a full on extra attack – Fighter 4th.
HD: 6,6,6,6 = 24 +4 = 28
Martial Archetype: Champion
Proficiency: (as multiclass) Medium Armor, Shields (never uses though), Martial Weapons,
Fighting Style: Two Weapon – Add damage bonus to off hand weapon
Improved Range: 19-20 is critical
Feat: Dual Wielder
Rogue capability (PRIMARY)
Predominantly a rogue, this would have been interspersed at various points of his career. While it hard to pinpoint exactly where all that would have been woven throughout character development. That said, it would always have been a level ahead of fighter – Rogue 6th.
HD: 5,5,5,5,5,5 = 30 + 6 = 36
Roguish Archetype: Mastermind (see Sword Coast Adventurer Guide)
Archetype Benefits: Disguise Kit, Forgery Kit, gaming cards, Dwarvish (speak/literate), Human (other); ability to mimic speech patterns of any creature after 1 minute of study; Help action as a bonus action (up to 30’ away)
Proficiency: Light Armor, Simple Weapons, hand crossbow, longsword, rapier, shortsword, Thieves Tools; Saves: Dexterity and Intelligence; Skills: Stealth (expert), Deception (expert), Investigation, Perception (expert)
Sneak Attack (3D6)
Feat: Sharp Shooter
Race: Half Elf
Proficiency: Common, Elvish, Human (dead language); Acrobatics, History (expert)
PROFICIENCY BONUS: +5
Lores (+2): Finance, Cormyr, Drow, Giants
Taught some spells and special knowledge – consider it a level of Wizard class
Whip – advantage on initiative if only wielding a whip, benefits of Dueling style wielding a whip, Extra attack; distracting strike + goading attack 1/short rest (d10/5)
Strength: He had no bonus, but a strength of 13 gives in in 5e.
STR = 11
Intelligence: He was quite smart, having a 16.
INT = 16
Wisdom: Not so wise, but wisdom treated slightly differently in 5e.
WIS = 13
Dexterity: Maximum ability.
DEX = 20
Constitution: He got a bonus with a 15 previously, but its a different scale in 5e.
CON = 13
Charisma: Indeed he had a good charisma, but not great. Intelligence was the primary mover over pure charisma.
CHA = 14
Sanity: We never played with sanity, but Rivkin definitely had several brushes with the edges of it and had trouble seeing the world the way others did. I would asses it as a slight penalty.
SAN = 9
Hit Points: Essentially its 28, 20 and 36. This is more than the previous character, so i dropped the original 13 CON to 11. That gives 84-14=70. Close to the old character. However, given the elevated damage output of 5e, the original 84 seems ok.
Poisons and Potions
Dust of Sneezing and choking x2, Potion of Animal Friendship, Potion of Gaseous Form, Potion of Water Breathing
2 braces of three throwing knives.
3 x normal w/poison
3 x mithril w/poison +2
Rapier (in 5e finesse – longsword in past)
+2, Sentinel power while wielded (advantage on wisdom/perception and initiative rolls)
Sentient: uses emotion to communicate; 30 feet senses range
Alignment: Lawful Neutral
Used with finesse
+2 dagger – tarnished, detects as non magical; poison
+2 (counts as +4 vs who can hit); D6 force damage
Powers of Rope of Entanglement (90’, entangles up to 3 creatures, DC 17, HP = 50)
Sentient: hearing/vision to 90’, transmits emotions,
Alignment: Lawful Evil (if wielder is as well, Vicious weapon – a critical does +7 damage)
Creator: Aberration (appears to move out of the corner of the eye)
Armor: Studded Leather (glamoured); +1
Lesser Shadow Cloak
(rebuilt from remains/tendrils of blown up artifact)
Advantage on Stealth (hide in shadows) checks
See in absolute darkness – magical or normal 120’
Cast darkness 1/day (double strength)
+2 passive perception vs. hide in shadows/stealth
Vanish in shadows/darkness 1/short rest (becomes invisible until moving or attacking)
Gray Bag of Tricks
Ring of Jumping
Amulet of Proof Against Detection and Location
Other items and stuff in various lairs
The second one violates the prohibition on having more than one, but was cast by a dragon with special knowledge.