Cheapest priced copy (Commander Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Hero's Blade 
Artifact — Equipment · Uncommon · Fate Reforged · #160
Equipped creature gets +3/+2.
Whenever a legendary creature you control enters, you may attach this Equipment to it.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
12 printings · $0.35 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2017 | 214 | Uncommon | $0.39 | — |
| Commander Masters | 391 | Uncommon | $0.35 | $0.49 |
| Commander Legends | 314 | Uncommon | $0.35 | $0.49 |
| Commander Legends | 464 | Uncommon | — | — |
| Dominaria United Commander | 186 | Uncommon | $0.35 | — |
| Final Fantasy Commander | 345 | Uncommon | $0.35 | $1.99 |
| Fate Reforged | 160 | Uncommon | $0.39 | $0.79 |
| Jumpstart 2022 | 776 | Uncommon | $0.35 | — |
| Marvel Super Heroes Commander | 201 | Uncommon | $0.35 | $0.49 |
| The List | C17-214 | Uncommon | — | — |
| Doctor Who | 241 | Uncommon | $0.35 | $0.49 |
| Doctor Who | 832 | Uncommon | — | $3.49 |
2 rulings from Wizards of the Coast
- 24 November 2014The triggered ability will trigger when one of the Gods from Theros block enters the battlefield only if your devotion is high enough that it's a creature when it enters. If Hero's Blade is attached to a God that stops being a creature (or any creature that stops being a creature), it will become unattached.
- 10 November 2020If the legendary creature that entered the battlefield leaves the battlefield before Hero's Blade becomes attached, Hero's Blade stays as it was. If it's already attached to another creature, it remains attached to that creature.