Nefarox, Overlord of Grixis

Flying is an evasion ability.

A creature with flying can’t be blocked except by creatures with flying and/or reach. A creature with flying can block a creature with or without flying. (See rule 509, “Declare Blockers Step,” and rule 702.17, “Reach.”)

Multiple instances of flying on the same creature are redundant.

Exalted is a triggered ability. “Exalted” means “Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.”

A creature “attacks alone” if it’s the only creature declared as an attacker in a given combat phase. See rule 506.5.