Regidrago VSTAR's attack is arguably the most unique in the game because it can copy the attacks of Dragon-type Pokmon in the discard pile
In this case, the spell side provides an infinite-hand-size emblem while drawing you lots of cards, and the Sea Gate, Reborn side is an untapped mana source if needed early on
To convey the idea that the hydras have a lot of heads and that you need to cut all of them off to kill the creature, these creatures usually have +1/+1 counters that are removed when the creature is damaged
Throwing a burn spell at an opponent
She is however everything I don't like in a creature, she is mana intensive to get most value from, she is gold making her narrow, she is a legend making her vulnerable, she offers no value at all when deal with on sight and doesn't really have any particular synergy with anything