Cheapest priced copy (Neon Dynasty Commander): $6.49 at Card Kingdom, near mint, their price list as of .
Akki Battle Squad 
Creature — Goblin Samurai · 6/6 · Rare · Neon Dynasty Commander · #57
Whenever one or more modified creatures you control attack, untap all modified creatures you control. After this phase, there is an additional combat phase. This ability triggers only once each turn. (Equipment, Auras you control, and counters are modifications.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $6.49 to $6.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Neon Dynasty Commander | 18 | Rare | $6.49 | — |
| Neon Dynasty Commander | 57 | Rare | $6.99 | — |
4 rulings from Wizards of the Coast
- 18 February 2022An Aura controlled by an opponent does not cause a creature you control to be modified.
- 18 February 2022A creature that is equipped is considered modified no matter who controls the Equipment that's attached to it.
- 18 February 2022A creature with a counter on it is considered modified no matter what kind of counter it is or which player put it on that creature.
- 18 February 2022Notably, the triggered ability of Akki Battle Squad doesn't give you any additional main phases. This means that you will move directly from the end of combat step of one combat phase to the beginning of combat step of the next one.