More about Antimatter Dimensions:
General Info: DimensionsTicksAchievements
Pre-Infinity: Soft ResetDimensional SacrificeAntimatter Galaxy
Pre-eternity: InfinityInfinity UpgradesChallengesAutobuyersBreaking InfinityInfinity DimensionsReplicanti
Post-eternity: EternityEternity MilestonesTime DimensionsTime StudiesEternity UpgradesEternity ChallengesTime Dilation
Misc: GuideTerminology

The CostEdit

They cost

n + (# of Galaxies * m)

8th dimensions, where n is 80 by default and reduced to 71 (inf upg), then 70 (ic5), and m is 60 by default and 52 with the relevant time study.

When you buy one, it will reset your run (like a dimension Shift or Boost), but the run will reset as if you never did a Shift or Boost.

The effect of getting a galaxy is to improve how much tickspeed you get per upgrade (see Ticks).

Hotkey for this is G.

Post-100 costEdit

Formula changes when you hit 100 Galaxies (note that this doesn't include those gained from Replicanti).

n + m*G + ((G-99)^2 * 2)

They still cost 8th dimensions even at that point.

Post-800 cost Edit

When you hit 800 Galaxies, galaxy cost starts to rise exponentially. The new formula for galaxy cost before subtracting is floor(n*1.002^(G-799)).

Challenge 10 cost Edit

Galaxies only cost 6th dimensions in challenge 10:

n + 19 + (# of Galaxies * 90)