C Common Frost and Flame Dragon X WATER Level 6 [ DragonEffect ] ATK 2300 DEF 2000 Cannot be Normal Summoned/Set
Graded Population Report: Entei #15 Visualize the distrbution of grades in the chart
C Common Triple Burst Dragon X DARK Link 3 [ DragonLinkEffect ] ATK 2400 DEF - 2+ monsters, except Tokens Once per turn, during the Damage Step, when a Spell/Trap Card, or monster effect, is activated (Quick Effect): You can negate the activation
Khrn the Betrayer Kharn the Betrayer is high on this list, not because I think it makes for a good commander, but because its an exceptional addition to other Commander decks that I like
The thing about mandatory effects is that it means your opponent can't negate the cards behind the mandatory effect
There are also some works by them that stand out, such as Aerodactyl V LOR 180