Unique Mob Farming
Beyond Scarab of Invasion
Effect: Unique monsters create additional Beyond portals, increasing your chances for lucrative drops.
Harbinger Farming
Harbinger Scarabs of War Hordes and Discernment
Effect: The War Hordes variant doubles currency shards dropped, while Discernment causes harbingers to drop a single type of currency shard, maximizing potential profit.
Legion Farming
Legion Scarab of Eternal Conflict
Effect: Allows for multiple breaks of Elden Ring Items Legion monsters, stacking additional reward tiles for increased loot.
Best Scarabs for Multiple Uses
Here’s a summary of scarabs that can be effectively used more than once:

Reliquary: 2 x 100% increased uniques
Divination: 2 x 150% increased divination cards
Torment: 4 x 5 additional ghosts
Anarchy: 4 x 4 additional rogues | 2 x 30% chance to Elden Ring Items for sale spawn a rogue giant
Ritual: 2 x rerolls with no cost, +1 reroll | 2 x 100% increased favor
Bestiary: 2 x 5 additional beasts
Harbinger: 4 x 3 additional harbingers
Abyss: 2 x additional abyss | 2 x 75% increased monsters
Essence: 4 x 2 additional essences
Domination: 4 x 2 additional shrines | 2 x 1 additional unusual shrine
Incursion: 2 x 12-16 additional packs of incursion mobs | 2 x 35% chance for mobs to be magic and pack size
Betrayal: 2 x 50% chance to drop a scarab
Blight: 2 x 20% chance to open a chest again
Breach: 4 x 2 additional breaches | 2 x 50% more breach splinters
Carto: 2 x 50% increased maps | 2 x 30% map duplication chance
Ambush: 4 x 5 additional boxes
Expedition: 2 x 100% increased runic monster markers
Legion: 4 x additional monoliths
Beyond: 2 x 30% increased merging radius
Ultimatum: 2 x 150% XP, rewards 2 tiers higher
Deli: 2 x reward meter fills 100% faster | 2 x 2 additional reward types
Misc: 2 x mirror packs, 3 x mysterious barrels