Random Number Generation, or RNG, is a highly debated topic in almost every competitive video game genre.

In the context of lane-pushing arena battlers, RNG is typically minimized compared to card games or auto-battlers.
Initial Deck Shuffling
If your opponent rushes the bridge and all your cheap defensive counters are at the bottom of your deck, you lose the tower.

By ensuring a healthy mix of low-cost cycle cards, they guarantee they will always have some form of defense.
Flexibility is a skill.Remove the guesswork from the mid-game.Some RNG is healthy for the game. Unit Targeting and Pathfinding
Sometimes a unit will retarget unexpectedly due to a micro-movement by another troop, completely ruining your defensive setup.

Leaving a slight margin for error in your defensive placements is the best way to handle AI unpredictability.
Genre TypeRandomness ImpactAuto-BattlersExtremely High - Relies entirely on shop rolls and item dropsStandard Tower RushHighly skill-dependent after the first 30 seconds The Mental Game
Getting angry at a bad starting hand only causes you to make further mistakes and lose the match entirely.

Focus on improving your timing and placement, and let the RNG sort itself out in the long run.