Cheapest priced copy (Planar Chaos): $0.35 at Card Kingdom, near mint, their price list as of .
Ridged Kusite 
Creature — Horror Spellshaper · 1/1 · Common · Time Spiral Remastered · #134
{1}{B}, {T}, Discard a card: Target creature gets +1/+0 and gains first strike until end of turn.
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Planar Chaos | 78 | Common | $0.35 | $0.49 |
| Time Spiral Remastered | 134 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 19 March 2021Causing a creature to gain first strike after first-strike combat damage has been dealt won't stop that creature from dealing regular combat damage.