There is match making systems that make pvp more fair,
For players level 1-5 Tutorial
For 5-10 Arena progress bar
From level 10 you will be entered into a tier based on level but possibly your wins and overall power. It's hard to know how these tiers are given I think they are just level based as tested each level advanced tier. The number of level from 10-19 fit into these tiers. Scout being 10 and Gladiator 19.
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Once level 20 is reached. A new tier system will appear. This is more detailed and points are needed to advance.