Normal Strategy:

Hunters: Grab a Handgun and a good Saber and/or Dagger. Use that Handgun to aim and shoot at the feet until its head comes down. Switch to either your Dagger or Saber and keep smacking the head. The Dagger might be your more powerful weapon at this point. After the Dragon gets smart and keeps its head up, use the Handgun to hit the feet and use the Saber/Dagger while it breathes fire.

Rangers: Grab a Rifle and a Saber. Smack the feet with the Rifle till its head comes down. If your Saber is more powerful, use that instead on the head. After that, just gun the feet for the duration of the fight.

Forces: Grab a Handgun and a Saber. Make sure you have Barta on your main configuration (when you don't have to hold down R to use it) and Zonde on your secondary configuration (when you do have to hold down R). Keep casting Barta until the head comes down. Now find out if your Saber or Barta is more powerful than the other, and continuously use it against the Dragon. When the Dragon flies up, pelter it with Zonde spells. Resume with Barta when it walks on the ground.

Hard/Very Hard Offensive Strategy:

Hunters: Use a Slicer! It'll hit 4 parts of the body for greater damage. Don't use Swords or Partisans.

Rangers: Use a Shot! It'll hit 5 parts of the body for greater damage. Keep using it for the whole fight! Use a Rifle-type weapon if you need to.

Forces: Use Gizonde! Avoid Gibarta! Gibarta wastes TP while Gizonde hits multiple areas.

Ultimate Offensive Strategy:

Hunters: Same deal as before.

Rangers: Same deal as before.

Forces: Use Foie, and avoid Gifoie! Gizonde still works here.

At the start, run to the Dragon's flank to avoid getting stepped on. Watch out to where you end up when you do your combo while it's moving around. If you're under the neck/feet area you won't get hit by it's breath weapon attack.

The flying breath attack is simple to avoid: either stay at the Dragon's back, or stay out of range by running under it or far away from it. Beware when it lands!

Once enough damage is dealt to the body or feet, the Dragon will fall to its knees and lower its head to the ground - be sure you are not under it when it does this!

If enough additional damage is dealt, the Dragon will roar and begin flying and starting its burrowing sequence of attacks. Don't be in the area where it dives. Also, any holes made by the Dragon will make little lava pits that will do damage. On Ultimate these will be ice pits that can freeze your character and do repeated damage.

Avoiding the three burrow attacks: make sure you have the mini-map on in a Multiplayer game so you can see where the attack is coming from. You can run around the outside perimeter of the map to help dodge. Aim to position yourself to be running perpendicular to its attack - in other words, run straight across the front of it. A curved path compromises speed in this case.

Sil Dragon tactic: after the second burrow attack, the Sil Dragon will sweep around the entire outside of the map, winding inward in a spiral pattern. To avoid, stand a fair distance away from the edge of the map after the second burrow attack. Once the mound passes completely by, run towards the edge of the map where the burrow just was. The next pass should miss you.

Again, avoid being under the Dragon when it lands. This goes for when it is killed in mid-flight as well.