It was a survivor of the original Dragon War that left the few surviving elder dragons
There aren't yet many good options, as it turns out, but while I'm not sure I'd call the RMS Titanic good exactly, it certainly is funny
Dockside is intended as a counter to Enchantment and Artifact-heavy decks, including other Treasure strategies, allowing a player to catch up in mana production without resorting to destructive options like Vandalblast
While the new Commander Masters cards are obviously built to mostly bolster the latest decks - namely an Eldrazi one, a Sliver one, a Planeswalker one and an Enchantment one - some will also make other decks, albeit ones that have similar themes for the most part, a lot better
If you do, return that card to the battlefield under its owners control at the beginning of the next end step