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

However, it still exists in subtle ways that can completely alter the outcome of a very close match.
Initial Deck Shuffling
Your starting hand is entirely random, which can immediately put you at a massive disadvantage against an aggressive opening.

Professional players build their decks specifically to minimize the chances of a truly unplayable starting hand.
Learn to adapt to bad RNG.Know what they are holding.Some RNG is healthy for the game. The Unpredictable AI
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.
Genre TypeRandomness ImpactDrafting GamesLuck is the primary factor in individual matchesStandard Tower RushHighly skill-dependent after the first 30 seconds Embracing the Chaos
The best competitors accept the chaos, focus on what they can control, and outplay the opponent regardless.

If you are stuck in a lower arena, it is because of your fundamental mechanics, not the random number generator.