If you open a card in a Golden Pack that you already have four copies of, duplicate protection will be handled in the following order: It will be replaced with a card from the same set of the same rarity you don't have four copies of
Earthbound Immortal Ccapac A
The Musketeer card has a Steel ink classification, meaning it's a strong card focused on defense

For all the cards I removed check the list below: Explorers of the Deep Cards Removed View on Archidekt Creatures (14) 1 Benthic BiomancerBenthic Biomancer 1 Coralhelm CommanderCoralhelm Commander 1 Deeproot EliteDeeproot Elite 1 Evolution SageEvolution Sage 1 Kiora's FollowerKiora's Follower 1 Merfolk SkydiverMerfolk Skydiver 1 Merfolk SovereignMerfolk Sovereign 1 Metallic MimicMetallic Mimic 1 Sage of FablesSage of Fables 1 SurgespannerSurgespanner 1 Thassa, God of the SeaThassa, God of the Sea 1 Thieving SkydiverThieving Skydiver 1 Tributary InstructorTributary Instructor 1 Vorel of the Hull CladeVorel of the Hull Clade Enchantments (1) 1 Simic AscendancySimic Ascendancy Instants (1) 1 Ripples of PotentialRipples of Potential Sorceries (1) 1 Bygone MarvelsBygone Marvels Making Waves Making a cut of 14 creatures in a typal deck may seem excessive until you take a look at the deck in its final form: 30 creatures, 10 instants, 6 sorceries, 11 enchantments, and 7 artifacts

This infamous boss monster of the deck in none other than, Number iC1000: Numerounius Numerounia
Every round starts with each player drawing something off the Threat deck, which, well, its all right there in the name