Garen comes to mind. Easy to play, good when used effectively.
No mana to worry about, no skillshots, pretty easy to itemize for, etc.
Annie or Ryze. They're not the strongest picks, but they're able to fit in many teams and are very simple mechanically.
Darius. Extremely easy to use, devastating to teams
Annie & Garen. Very very low skill cap, very high reward for it.
Mechanically? Mordekaiser. Mordekaiser is the thinking-man's champion. He's all about game sense. Knowing where to be and what to build. He requires thought, but not fast fingers.
Vladimir. You Q when they're near and ult in teamfights. You pool to escape.
Jax. Just auto attack and E when you're getting hit.
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