Riolu

Riolu (112/198), the Common from Scarlet & Violet, has an estimated ungraded market price of about $0.20. Note: 28 other cards named Riolu exist across the sets Riffle tracks, at very different values; check the collector number.

This page covers Riolu (112/198), the Common (about under $1) from Scarlet & Violet.

The other versions: #215/198 from Scarlet & Violet (Illustration rare, about $29–$38); #173/91 from Paldean Fates (Shiny rare, about $11–$15); #GG26/70 from Crown Zenith Galarian Gallery (Rare, about $11–$15); #61/130 from Diamond & Pearl (Uncommon, about about $1); #117/146 from Legends Awakened (Common, about under $1); #91/127 from Platinum (Common, about under $1); #75/135 from Plasma Storm (Common, about under $1); #76/135 from Plasma Storm (Common, about under $1); #79/113 from Legendary Treasures (Uncommon, about under $1); #63/99 from Next Destinies (Common, about under $1); #50/95 from Call of Legends (Uncommon, about under $1); #116/236 from Unified Minds (Common, about under $1); #102/214 from Unbroken Bonds (Common, about under $1); #115/236 from Unified Minds (Common, about under $1); #60/95 from Unleashed (Common, about under $1); #45/124 from Fates Collide (Common, about under $1); #46/124 from Fates Collide (Common, about under $1); #66/156 from Ultra Prism (Common, about under $1); #076/132 from Mega Evolution (Common, about under $1); #050/131 from Prismatic Evolutions (Common, about under $1); #70/147 from Burning Shadows (Common, about under $1); #078/172 from Brilliant Stars (Common, about under $1); #113/198 from Scarlet & Violet (Common, about under $1); #90/185 from Vivid Voltage (Common, about under $1); #071/159 from Crown Zenith (Common, about under $1); #112/217 from Ascended Heroes (Common, about under $1); #081/142 from Stellar Crown (Common, about under $1); #SV21/94 from Hidden Fates Shiny Vault (Shiny rare).

The collector number printed at the bottom of the card is the reliable way to tell them apart.