Exhaust- Useful in matchups vs AD champions who have bursts with decent CDs. If you do this when theytry and burst, their damage is dropped greatly and you gain a HUGE advantage in a fight.

Ghost-Good vs fast champions (Ones you will need to chase for an extended period) IE: Nidalee

Heal- Useful for baiting your enemy into moves, allows you to aid your team in teamfights.

Revive- Shen and Pantheon only.

Smite- Just no.

Teleport- Good spell if you are ORGANIZED with your team. You can use this spell to coordinate plays, go back and buy without missing any xp, or to split push and still aplly pressure on the enemy team.

Cleanse- You wont really need this spell 99% of the time, nice vs a CC heavy enemy team for the tenacity it gives.

Promote- Only for karma (She can support the super minion with all her spells xD)

Clarity-not that useful of a spell. (NOT RECOMMENDED)

Ignite- Allows you to burst enemys down without them expecting it, also lets you pick up the kill after they flash xD.

Clairvoyance- Not really needed on you.

Surge- [Jax]], Kayle, and Fizz and still then even not that great

Flash- Good for champions that need placement INSTANTLY, stronger spell on burst champions who ,with that distance, can kill you.