Explore by itself is a ton of value -- you guarantee your next land drops and are buffing your army -- but it's especially good here due to synergy potential with +1/+1 counter payoffs (Tributary Instructor) and graveyard payoffs (Deeproot Historian)
Ill put some of the highlights in order, then gold, just for people to know what they can expect out of these: Kenrith, the Returned King Akroma's Will Urza, Lord High Artificer Counterspell Cryptic Command Rhystic Study Yawgmoth, Thran Physician Bolas's Citadel K'rrik, Son of Yawgmoth Ragavan, Nimble Pilferer Ancient Copper Dragon Primeval Titan Atraxa, Grand Unifier Tymna the Weaver Isshin, Two Heavens as One Thrasios, Triton Hero #45
Kingjim tefrenu (~$7) - capacity: 40 sheets I love that theres only 4 rings on the top and bottom, so the rings are not in the way when I write
The Rising Rampage booster set introduces 100 all-new cards and brings with it two new monster themes: Blue Maidens Marincess from Yu-Gi-Oh