Cheapest priced copy (Commander 2021): $0.49 at Card Kingdom, near mint, their price list as of .
Geometric Nexus 
Artifact · Rare · Commander 2021 · #77
Whenever a player casts an instant or sorcery spell, put a number of charge counters on this artifact equal to that spell's mana value.
{6}, {T}, Remove all charge counters from this artifact: Create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is the number of charge counters removed this way.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.49 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2021 | 77 | Rare | $0.49 | — |
| Commander 2021 | 404 | Rare | $0.99 | — |