Aurelius ducks under the troll's claw, but its disgusting fangs manage to find a seam in his armor and wound him (you need to roll critical hit damage).

As the troll turns away, Aurelius ripostes the attack with his flame tongue longsword. (Reaction, round 1)

Attack: 12 Damage: 11 magical slashing damage + 2 fire damage.

(Edit- second attack roll for advantage: 10)

(OOC: Don't forget advantage from faerie fire  :-)

(Yes, I did miss the critical.  Damage to Aurelius: 3 pierce)

(And yes, Aurelius would have advantage on the attack.)

Rahkeshi quickly calls out "Rapid Retreat" in Druidic as she casts Expeditious Retreat. She then transforms into a black bear, passing by Elyria and coming directly up to the troll.

(It is now Aurelius' turn. Plus can still roll again for the advantage on the previous reaction - the present roll would have missed.)

Assumming the troll is still heading for Rahkeshi when Elyria is up.

"You stay away from her!" Elyria growls at the troll. Then she swiftly transforms into a large black bear, ready to defend her family from any dangers, any, lumbering forward towards the troll.
The black bear attacks the troll in rage.
Bite: 17 Damage: 3
Claws: 8 Damage: 8

(Elyria will need to re-do her turn for this round.  Wild Shape requires an Action, so you could not do an attack after.  It is why Rahkeshi did not attack last round. At least that is my understanding - feel free to tell me if I'm wrong!)  

(OOC: No you're correct of course, my bad, editing and sticking with just the wild shape.)

Aurelius round 2

The paladin swiftly charges after the troll, muttering a mystical curse in Elvish (casting hex as a bonus action, causing DA on STR ability checks), and hewing at its limbs with his flaming sword.  His eyes gleam with something like... joy? Perhaps from the thrill of combat.

Attack: 25 Damage: 9 magical slashing+ 4 fire damage + 2 necrotic damage

The troll seems to focus on Rahkeshi in bear form, clawing and biting at her.

(Claw: 12, Damage: 11 slash)

(Claw: 21, Damage: 7 slash)

(Bite: 21, Damage: 5 pierce)

Both swipes of the troll's claws batter the black bear and send it reeling to the ground gravely wounded.  It reverts back to the form of the half-orc.

The troll's teeth then find Rahkeshi's shoulder,  piercing the flesh there.

(Rahkeshi CON Save for Concentration: 10, 22, 14)

Rahkeshi collects herself and calls out "Enhance" in Druidic to cast Shillelagh. She then attacks the troll with her staff. 

(Attack: 8, Damage: 6)

Although Aurelius' attack hit, the troll still seems to be in good condition. Rahkeshi's attempt misses the creature.

(Next round - Aurelius up)

Round 3

Aurelius glances quickly at the half-orc.  "Rakeshi, you ok?"
He then taunts the troll, "Thou putrid mass, thou fetid pile of dung, prepare to be sent to the afterlife by Aurelius... the Magnificent!"

Attack: 13 Damage: 8 magical slashing+ 5 fire damage + 6 necrotic damage

With a GROWL the remaining Black Bear furiously attacks the seared troll.
Bite: 7 Damage: 5
Claws: 13 Damage: 8

Aurelius' blow again strikes the creature, which is now showing signs of wounds. The bear's attacks do not manage to hit it however.

The troll continues to try to bite at Rahkeshi, but this time swings a claw at the others two now attacking

(Bite v Rahkeshi: 15, Damage:5 pierce)

(Claw v Aurelius: 26, Damage:6 slash)

(Claw v Elyria: 25, Damage:8 slash)

Rahkeshi says,  "I'm fine," just as the troll manages to briefly bite her forearm. She mutters, "Bracelet - Entangle" in Druidic to cast Ensnaring Strike then attacks the troll again with her staff.

(Attack: 9, Damage: 6 bludgeon)

(Troll STR Save if hit: 9)

Rahkeshi's blow misses again.  The troll still appears wounded but more than able to fight.  Rahkeshi seems to have a little blood on her arm, but also seems ok.

(Round 4 - Aurelius is up)

The troll's claw attack catches Aurelius on the left hip, at the seam of two armor plates.  He winces in pain as his flesh is torn by the filthy, ragged nails.

Round 4

"Que c’est laid! Even for a troll, you are disgusting. I will rid the world of your nauseating presence!  Turn and face me, you cowardly wretch!"

Longsword Attack: 22 Damage: 5 magical slashing+ 4 fire damage + 2 necrotic damage  (still assuming ADV due to faerie fire).

The Black Bear growls as the troll claw tears into its body. (Black Bear hp 11/19) (Con save for faerie fire: 8 success, I think)
It retaliates furiously with claw and bite of its own.
Bite: 20 Damage: 7
Claw: 20 Damage: 8

(Yes, DC 10, so Elyria keeps concentration on Faerie Fire.) 

Aurelius successfully hits the troll once again this time squarely in the side. And while the black bear's bite misses the troll, her claws rake across one leg. 

The troll turns its attention a bit more towards Aurelius, biting and clawing at him.  It again takes a quick swipe at the black bear as well. 

(Bite v Aurelius: 8, Damage: 5 pierce)

(Claw v Aurelius: 8, Damage: 11 slash)

(Claw v Elyria: 25, Damage: 15 slash)

(CON Save for Ensnaring Strike: 3.)

Rahkeshi again tries to strike the troll with her staff. "Hey! Are you ignoring me now you stupid creature?"

(Attack: 21, Damage: 9 bludgeon) (Troll STR Save, if hit: 24)