Players who treat the game purely as a test of reflexes will inevitably hit a skill ceiling they cannot break without learning the underlying mathematics.

To truly master the genre, you must stop looking at units as 'characters' and start viewing them as numerical investments.
Generation Rates and 'Leaking'
The only way one player can mathematically gain an advantage is if the other player 'leaks' elixir by sitting at the maximum cap of 10.

This is why top players are constantly 'cycling' cheap cards in the back of the arena; they are ensuring the generation timer never stops ticking.
Protect them fiercely.The 'first play' dilemma is real.Tracking generation is just as important as tracking spending. Winning the Economic War
The entire goal of defensive play is to execute 'positive elixir trades', where you spend less energy to destroy a push than the opponent spent to create it.

If you consistently make negative trades, you will eventually find yourself trying to defend a massive push with absolutely zero elixir in your bar.
Advanced TacticHow it WorksThe Kiting TradeUsing a 1-elixir Skeleton to pull a 4-elixir Mini P.E.K.K. For more info in regards to tower rush check out our site. A across the map until both Princess towers shoot it to death; +3 profitMulti-TargetingWaiting until the opponent places three different support troops near their tower before dropping the Rocket, destroying 12 elixir with 6; +6 profit The Invisible Scoreboard
You should always know exactly who is 'up' in elixir at any given moment.

Launch your win condition, support it with a spell, and watch them fail to defend because they simply do not have the currency to buy troops.