Cheapest priced copy (Foundations Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Thopter Spy Network 
Enchantment · Rare · The Brothers' War Commander · #97
At the beginning of your upkeep, if you control an artifact, create a 1/1 colorless Thopter artifact creature token with flying.
Whenever one or more artifact creatures you control deal combat damage to a player, draw a card.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
9 printings · $0.49 to $6.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The Brothers' War Commander | 97 | Rare | $0.69 | — |
| Commander 2018 | 107 | Rare | $0.69 | — |
| Aetherdrift Commander | 83 | Rare | $0.59 | — |
| Foundations Commander | 79 | Rare | $0.49 | — |
| Jumpstart 2022 | 361 | Rare | $0.59 | — |
| March of the Machine Commander | 241 | Rare | $0.59 | — |
| Neon Dynasty Commander | 98 | Rare | $0.69 | — |
| Magic Origins | 79 | Rare | $0.79 | $6.99 |
| Magic Origins Promos | 79s | Rare | — | $4.99 |
2 rulings from Wizards of the Coast
- 22 June 2015The last ability will trigger, at most, once per combat damage step per player. However, if at least one artifact creature you control has first strike and others don't, or if an artifact creature you control has double strike, the ability could trigger twice per combat: once in each combat damage step.
- 22 June 2015Thopter Spy Network's first ability has an “intervening ‘if' clause.” That means (1) the ability won't trigger at all unless you control an artifact as your upkeep begins, and (2) the ability will do nothing if you don't control an artifact as it resolves.