
Lore:
20 year old (yes, 20) Luigi Romano, son of first generation Italian immigrant Vincenzo Romano (owner of the Cursed Apple's famous Vinny's pizza), has always been able to see spirits. He never thought much about them until his 18th birthday when they convinced him to play the stock market under their guidance instead of continuing to work in his father's pizza shop. He's made good money but his business partners take a substantial cut. After an incredibly stressful two years of day trading, Luigi is looking for an escape and looks to the ritual to secure financial stability and get a retirement plan.
Voice lines with other characters would mostly revolve around their occupations, Luigi asking what their retirement plans are like and etc. An interaction probably with Apollo, who Luigi considers a peer due to their close ages, would revolve around Apollo assuming he is much MUCH older. Also a potential future pizza delivery character could work at Vinny's and have interactions with Luigi relating to that.

Deposit (1):
Luigi swings a bag of money around him and tosses it. Doing damage and knockback with the swing and higher damage when it hits the ground. It does lingering damage over time before being pulled into the ground by ghostly hands
While off CD, accrued souls increase the damage by up to double.
Upgrades likely include increased scaling, decreased soul accrual requirement, and a stun effect when making a max deposit.

Ghostly Guidance (2):
Luigi briefly (very brief) becomes ethereal and is able to fly.
Passive: All spirit damage Luigi deals applies a stack of a movement slow debuff
Upgrades likely include increased duration/decreased cooldown, increased passive slowing effect.

Long/Short (3):
After a short delay, Luigi applies a buff or debuff to the target hero depending on their team. Allies receive movespeed and firerate, enemies lose bullet/spirit res.
When a hero affected by Long/Short gets a kill or is killed, the killer receives a few permanent buffs. Luigi additionally receives the buffs if the killer is an ally (double if self)
Upgrades likely include more buffing/debuffing on the ability, cd/duration, and more permanent buffs for the killer/Luigi.

Great Depression (4):
Luigi breaks down in anxious rambling for a while. Enemies that remain within earshot (ignores LOS) deal reduced damage and also receive additional spirit damage from Luigi's bullets.
Upgrades likely include area/cd/duration, a bonus slowing effect (separate, thus stacking with 2's passive).