Shadow Roxas

The Shadow Roxas is an enemy fought near the end of Roxas's story in Kingdom Hearts II.

Kingdom Hearts II
When investigating the Seven Wonders of Twilight Town, Roxas checks up on the "Shadowy Doppelgänger" myth, and ends up in front of a waterfall. He sees a reflection of himself, which turns into a dark Roxas clone and engages in battle with him. Shadow Roxas is last seen in Kingdom Hearts II after Roxas and friends leave the waterfall, peering out ominously until dissipating into nothingness.

Strategy
Shadow Roxas is very easy in the fact that he only has one ability on him and that is Combo Boost. He uses a Struggle Bat against Roxas. So the simplest way is to Guard or deflect his attacks then hack at him. However, it does not give any experience once it is defeated.