It is 14 uncounterable damage with just one Blood Artist effect in play which means tapping out as a control deck, even with Force of Will up, is risky business
Alternatively you can make a threat as likely to end the game as Monger for cheaper that also does nothing else such as Phyrexian Obliterator, Master of Feasts or even just classic old Tarmogoyf
Ultimately, it will come down to the prevalence of planeswalkers and battles as well as how many two toughness or fewer creatures are being played
The Spelunking causes your lands from Reef to come into play untapped, giving you the mana to cast another Master of Waves or Glasspool Mimic
If you ever find a way to clone an Enduring Scalelord with Dacks Duplicate you can live a beautiful dream
A 1st Edition graded 10 is valued at approximately $11,000, but copies featuring the distinct error splotch command even higher premiums