If you kept Confuse Ray on your Golbat, you can try to cheese through the fight via confusion damage with save states. Golbat needs to be able to outspeed Maroghost (if you've been holding onto that Jolly Mint...), but once it does, this will let you skip its turns and stack other damage onto it. If Golbat still has Poison Fang, this will be the point you should gun for inflicting badly poisoned status on Maroghost.
Obtaining Focus Band(s) and Quick Claw(s) can also aid in pushing through this fight with luck mechanics. Focus Band gives mons a 10% chance to survive any fatal hit, whereas Quick Claw lets mons go first 20% of the time. Wild Machop (enter Rock Tunnel from the Lavender side and search on that same floor) have 5% odds to hold Focus Band and wild Meowth (among other places, Route 8, west of Lavender, inside that enclosed space via Cut) have 5% odds to hold Quick Claw.
If you choose to go item hunting, you should get a Butterfree. Not only can it be taught Thief (via a TM that's found in Mt. Moon), its Compound Eyes Ability turns those 5% odds into 20% odds. Fly to Cerulean City (Fly is found in the house past the Cut tree on Route 16, west of Celadon City), head north to Route 25 and go to the grass once you've crossed Nugget Bridge; Caterpie can be found there.
This isn't as helpful for this fight as it might seem, as the best source of experience during this part of the game comes from the boss and mini-boss trainers, like Mr. Fuji and Cultist M. If a player knows to do this beforehand, they can purposefully lose to a trainer's last Pokemon to gradually gain experience; but that's only useful until that trainer has been beat. Plus, Pokemon Tower is an awkward/bad place to do that due to having to constantly go back up all them floors (even with encounter rates being so low there not that finding a Pokemon while travelling up and down the floors is very realistic).
And unfortunately, wild encounters nearby are too low-Leveled with too low experience gains to be of any feasibly timely use. (If I'm not mistaken, the highest gains at that point are the highest-Level wild Voltorb on Route 10, if luck has them spawn in that high range. and that's still around 230-ish at most.)
In addition to what I just wrote, being Level 35 alone will not guarantee anything against Maroghost. It's a game-original fan-made Pokemon with ridiculously kitted stat spreads that has Earthquake, Thunder Punch, Ice Punch, and Shadow Sneak. Most teams will only be partially fully-evolved, meaning they'll be outsped by and hit with a 75-100 power move they're weak to (and even if not, Maroghost's sky high Attack means it typically won't matter). It's weakest move is Shadow Sneak, but its stats versus what the player will have means it's still gonna hurt and possibly one-shot whatever it gets used against.
All this to say, increasing Levels, both on its own and in general, isn't going to cut it as workable advice here. The only exception is maybe for Pokemon with naturally high Speed, like Golbat, so it can outspeed Maroghost for the purposes of sticking a debuff on it of some kind.
(Frankly,
@-Dragonsden- , this boss fight needs to be nerfed. It's too strong for this part of the game where the player's tools are too limited, particularly since the Deep Base and its resources is opened
after this fight.)
![[PokeCommunity.com] Pokémon Team Rocket Edition: Dragonsden Version - Kanto/Sevii/Johto | Next release: DLC (season 4)](https://data.pokecommunity.com/attachments/89/89284-da532832358dcd35b0d69d9a61a6aac5.jpg "[PokeCommunity.com] Pokémon Team Rocket Edition: Dragonsden Version - Kanto/Sevii/Johto | Next release: DLC (season 4)")
