Seven mana for a 4/4 flier usually means youre getting some kind of useful ability or keyword on top of the vanilla creature
Gold-Forge Garrison Gold-Forge Garrison Dunes of the Dead Dunes of the Dead Gargoyle Castle Gargoyle Castle Cradle of the Accursed Cradle of the Accursed Dark Depths Dark Depths Foundry of the Consuls Foundry of the Consuls Sliver Hive Sliver Hive Springjack Pasture Springjack Pasture Urza's Factory Urza's Factory Gods' Eye, Gate to the Reikai Gods' Eye, Gate to the Reikai Westvale Abbey Westvale Abbey Tomb of Urami Tomb of Urami Kher Keep Kher Keep Hellion Crucible Hellion Crucible Grove of the Guardian Grove of the Guardian
My big picks for this deck are Sword of War and Peace and Molten Psyche, which can do some serious damage
The efficiency here will just put a really fast clock on your opponent, and I think thats enough for it to get into the lower range of bomb territory
Lapras ex seems like a strong card, but it doesn't appear so overwhelmingly powerful that it would impact the overall game
Packs with multiple rare cards do come up, but for the drop rate, take this update from Mark Rosewater