The presence of luck-based mechanics in a strategy game can be both a blessing and a massive frustration.

In the context of lane-pushing arena battlers, RNG is typically minimized compared to card games or auto-battlers.
Initial Deck Shuffling
Your starting hand is entirely random, which can immediately put you at a massive disadvantage against an aggressive opening.

Once the initial hand is played, the rotation becomes fixed, and pure skill and memory take over.
Never run a deck that is too heavy.Cycle your cheapest cards in the back.It happens to everyone. Unit Targeting and Pathfinding
Sometimes a unit will retarget unexpectedly due to a micro-movement by another troop, completely ruining your defensive setup.

Relying on a unit's aggro range down to the exact pixel is risky because tiny bumps can alter their trajectory.
Game StyleRandomness ImpactAuto-ChessExtremely High - Relies entirely on shop rolls and item dropsStandard Tower RushVery Low - Only the starting hand is randomized Embracing the Chaos
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.