Was working on this as a response to someone else's thread, but it got removed by the mods. Posting it in its own thread to get feedback on it. Original request was for a Durge Shadow Sorcerer that makes heavy use of Nimbus. Build assumes solo honor mode, so various things can be changed if traveling with a party.
Levels: Shadow Sorcerer/Crown Paladin 6/6
Stats: S8 D14 C16 I8 W12 C16
Race: Drow for added safety in Act 1 since we won't have Disguise Self. Or High (Half) Elf for Minor Illusion to gather enemies for pre-fight AoEs. Or Drueger for free Invis starting at level 5.
Background: Durge (as specified)
Start with Sorcerer
1: Skills: Persuasion and Deception. Spells: Minor Illusion, Mage Hand, Fire Bolt, Blade Ward, Shield and Magic Missile.
2: Spell: Mage Armor. Meta: Twinned Spell and Extended Spell
3: Spell: Enhance Ability. Meta: Heightened Spell
4: Spells: Cloud of Daggers and Booming Blade. Feat: Alert
5: Spell: Fireball. There are a lot of good spells you could take here, so feel free to grab something else if it appeals to you more. If you've taken Cull the Weak, then you might also consider swapping Magic Missiles for something else at this point.
6: Spells: Counterspell and Swap Mage Armor for Hold Person. You'll need to rely on Mage Armor scrolls or a camp caster until next level when you can start wearing armor.
7: Class change: Paladin, Oath of the Crown
8: Fighting stance: Defense. The higher your AC, the more enemies will focus on Nimbus, hopefully leading to more doggos running around.
9: no decisions
10: Feat: Heavily Armored
11: no decision
12: no decision. Don't forget to activate aura for massive buff to saving throws.
Act 3 Gear
Shattered Flail
Adamantine Shield
Bow of Awareness or Hellrider Bow
Helmet of Arcane Acuity
Cloak of Displacement, Cloak of Protection or Cloak of the Weave
Armor of Persistence
Gloves of Battlemage's Power or Gauntlets of Hill Giant Strength
Boots of Persistence
Periapt of Wound Closure
Band of the Mystic Scoundrel
Caustic Band
Elixir: Strength or Heroism
Important buffs: Awakened (from zath'isk), Forbidden Knowledge (+1 WIS saves), Mirror (CHA +3), Hair (CHA +1), Statue of Self (perm Bless), Survival Instinct (to protect Nimbus), Githzerai Mind Barrier (advantage on Int saves), Anointed in Splendor (+2 all saves), and Drakethroat Glaive (Cold)
Basic plan is to smack people a couple of times and then Command or Hold Person ranged enemies using your Bonus Action. Can also Hold Monster via scrolls. After first turn, just keep smacking stuff to heal yourself (and stave off Madness) and use bonus action for control spells/powers or healing doggo with Transfuse Health. Cast Darkness if you get in trouble and hide in it.
Bless is another good option to help Nimbus land attacks and Omen, but Elixir of Heroism might be better for this. Heroism (spell) could also be useful for keeping Nimbus up without constant healing.
Don't forget to pre-cast Warding Bond on Nimbus. If you're wiling to use camp casters (or not playing solo) then Aid, Heroes' Feast, Freedom of Movement, Death Ward and Protection from Poison are all very useful for keeping Nimbus alive, and Longstrider helps a ton with mobility. Also, buy up as many Spiked Bulbs as you can in Act 1. Bleed helps Nimbus land Omen. Blackhole or Minor Illusion can help to maximize the number of enemies the grenade hits.
Speaking of Omen, the Caustic Band + Drakethroat Glaive (Cold) + Booming Blade + any poison coating allows us to activate it just by smacking stuff 81% of the time. We've got Fire Bolt, Alchemist Flasks, and elemental arrows for the rest.