If two or more cards are tied for highest cost, the target or targets remain unchanged
As with any type of competition, watching the best play motivates everyone to try to reach their level and show what they can do
These are the most consistent decks in Standard and the most played on the Arena Ladder: Izzet variations (prowess, elementals, lessons): These decks all play a lot of blue and red cantrips/burn/lessons to fill their graveyard and exploit synergies, like lessons in the graveyard, cost reduction, or elemental creatures
Its important to note that Frank is not describing the ideal number of sources for a given set of spells, hes describing the minimum , by his definition
In the current format, there are numerous ways to return Pokmon to the hand, and this is usually a great way to remove damage from the board and stop the opponent from taking prize cards