What are you trying to achieve with this
AOS goblin army? Win all the time? Or a large cohesive force based around either Common Goblins (
Gitmob) or Night Goblins (
Moonclan)? I'
mm go with the cohesive force, because that makes more sense for
AOS
So let's say you have to choose between Gitmob or Moonclan, without doing any Counts As between the two - converting up a Squig Gobba to use as a Doom Diver, for example - and without using any of the non-aligned
Grots (basically the Forest Goblins riding on spiders of different sizes) or big things (classically Giants are more of a Gitmob thing and
IMHO Trolls more Moonclan). Since you've just got 100 wounds to work with (right?) that shouldn't be a problem - for the record, I recommend using SDK or a pool system, though you're going to end up with a MUCH larger army ... as you should, both of these are horde armies!
Anyway, let's look at the scrolls available:
GITMOB WARSCROLLS Grom the Paunch
Goblin Warboss
Goblin Shaman
Goblins
Goblin Wolf Riders
Goblin Wolf Chariots
Goblin Spear Chukka
Doom Diver Catapult
Nasty Skulkers
Snotling Pump Wagon
Great Gitmob Formation 1 Warboss
1 Shaman
1 Chariots / Wolves
3 Goblins
1-3 Skulkers
Ravening Hordes: +1 to hit against a unit with fewer models; +1 to wound against a unit with 1/2 or less models
Da Boss Is Going Up In Da World: It the Warboss slays a hero or monster, no one in the formation takes Battleshock tests any more
I think if you choose either Gitmobs or Moonclan you should totally build your army around their formation. The minimum Great Gitmob looks like:
1 Warboss
1 Shaman
1x 1 Chariot
3x 10 Goblins
1x 1 Skulker
-------
43W
And it's also pretty unimpressive. I'd double to triple the Goblin units, swap the chariot to a unit of Wolf Riders (because the Goblin Chariot went from being awesome in 8E to really not good in
AOS, unless I'm missing something), buy more Skulkers and invest in an artillery piece out of formation. More experienced Goblin players can help, although I find I run up against 100W extremely easily
Either way, let's move to ...
MOONCLAN WARSCROLLS Skarsnik, Warlord of the Eight Peaks
Night Goblin Warboss
Night Goblin Warboss on Great Cave Squig
Night Goblin Shaman
Night Goblin Fanatics
Night Goblin Squig Hoppers
Night Goblin Squig Herders
Mangler Squigs
Cave Squigs
Great Moonclan Formation 1 Warboss
1 Shaman
1 Hoppers or Manglers or Cave Squigs
3 Night Goblins
1-3 Fanatics
Fungus Brew: All models get +1 Bravery; all 6+ to hit = make an extra attak
Hooded Villain: Warboss rerolls any hit dice, but you have to wear a hood or beat your opponent in a staring contest (

)
Arguably better formation bonuses - though the Gitmob's are solid, these happen all the time (but you gotta wear your hoodie

). Min looks like:
1 Warboss
1 Shaman
1x 5 Hoppers
3x 10 Night Goblins
1x 1 Fanatic
-------
49W
Or something like that. Again, you want larger units across the board, also some Mangler Squigs because they're amazing
and benefit from the formation! And again, your wounds are going to evaporate - your goblin horde of either flavor will benefit greatly from any other balancing system.
Which would I choose? Moonclan hands down. Gitmob have some decent synergy and some scary advantages for fielding big hordes of Goblins with the formation bonuses, plus artillery if you're being a purist ... but Moonclan has more units that just seem better, with formation bonuses that are easy to achieve, better / newer models, and synergy of their own. Plus Skarsnik if you want to rock a special character.
Again, Goblin experts are welcome to step in and help, refute, etc. Just feel like Moonclan has more options if you want to go pure one or the other, plus might be able to pull off a 'better' 100W cap when including their formation.
EDIT My attempts to make 100W lists with a formation are below ...
- Salvage