Because the match ends the exact millisecond a tower hits zero hitpoints, certain cards become exponentially more valuable, while others become complete liabilities.

A massive, slow-moving Golem that takes thirty seconds to cross the map is often useless in a panicked Sudden Death scenario.
The Spell Cycle Enders
The Rocket is the absolute king of Sudden Death; it deals the highest burst damage in the game, capable of taking nearly 600 hitpoints off a tower instantly.

The Lightning spell is the secondary option; while it deals slightly less damage than the Rocket, it deploys almost instantly and has a massive radius, making it impossible to miss.
The Fireball is great for chip damage, but it takes 3 or 4 cycles to kill a healthy tower in overtime.If the opponent is spell cycling you, you must pressure them so heavily they cannot afford to spend 6 elixir on a spell.If you cast Poison, they might cast a Rocket and win before your Poison finishes ticking. Fast Damage in Overtime
The Miner is the quintessential Sudden Death troop; because he tunnels underground, he can be deployed directly on the enemy tower instantly.

In Sudden Death, speed and unpredictability are vastly superior to raw stats and massive hitpoints.
Sudden Death CardThe Overtime AdvantageThe DangerThe MinerCan be placed instantly anywhere; bypasses all ground defenses and guarantees chip damage if the opponent predicts wrongLow Risk; only costs 3 elixir, leaving plenty of energy for defenseThe Freeze SpellStops all enemy defenses for 4 seconds; if you have even a single Skeleton near their tower, Freeze guarantees massive damageExtreme Risk; if it fails to take the tower, you wasted 4 elixir and they have a massive counter-push ready The Clutch Mindset
The player who panics and throws a desperate, unsupported push will almost always lose to the player who calmly executes their win condition.

Leave the panic to your opponent.

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