Stronger creatures on board lessen the chance of opponents blocking and losing their staple components
Locthwain Paladin Right off the bat, we have Locthwain Paladina card that could have easily been a rare in Alpha simply for it being better than the uncommon Bog Wraith in many respects
SR Super Rare UR Ultra Rare SE Secret Rare UL Ultimate Rare PS Platinum Secret Rare CR COLLECTOR'S RARE QCSE Quarter Century Secret Rare Ancient Gear Fortress X SPELL Continuous During the turn they were Normal or Special Summoned, your opponent cannot target "Ancient Gear" monsters you control with card effects, and they cannot be destroyed by your opponent's card effects
I will be able to get to everyones suggestions eventually
Perhaps we'll go back to 15 mythics per set in the future, although it's also possible that Hasbro likes the fact that more mythics means players need to open more packs (and spend more money) on Arena to complete a set and that the change will remain even when MDFCs are no longer in every set
Tornado Dragon Similar to how Lunalight used to be able to exploit Tiger during either turn with Tornado, you can use it here to trigger equipped Gadgets or Urgent Schedule