Melt your enemies with the power of the sun

Items
Pros/cons
Skills
Jungling
Team work

The key to the pure damage build order is gain magic power early so you can maximize the effectiveness of the polynomicon. The polynomicon is really the key to this build because of its added ability. After you use an ability, your next basic attack will get a damage bonus based on your magic power. This basically adds another nuke to Ra's repertoire, which he badly needs to finish off enemy gods. With this build you initiate the fight with your divine light, slowing your opponent to a crawl. Then cast solar blessing on your slowed opponent, run into your solar blessing to buff yourself - your opponent will most like be running to get out of the circle to stop taking solar damage, then slam him with your celestial beam. If your opponent still stands basic attack him, and with the help of your polynomicon, he will most likely be downed. Against tankier gods you may need to pop divine light, solar blessing, then basic attack, wait a second, then celestial beam, then auto attack again. This allows you to get two procs from the polynomicon, and with this build you should have 600+ magic power by the end of the game, so these two extra nukes will drop, or come close to dropping the tankier gods, if not rinse and repeat. The patch hurt this build a lot, because it moved the cd buffs, which are great for ra out of the middle lane. For this reason a chronos pendant or breastplate of valor, based on the situation, may be substituted for your obisidian shard.

When laning against Anubis, or playing games against gods with a lot of stuns I grab the reinforced boots. I rarely buy the purification beads (unless playing against hades) because of their 2 minute cooldown (anubis' mummify has a cd of 12 seconds...). I then grab a doom orb to make up for the magic power you lost in your boots, in hopes that your tanky boots will help you survive and not lose your stacks. The build then follows a similar pattern, relying on the polynomicon for added damage.

If you prefer a tankier style of play, or your team needs it, go with the tank Ra build. This build is gaining popularity. Tking the stone of gaia will give you a very tanky start, with some mp5 for lane sustain. This build is more of a support build, and can really annoy opponents with his constant heals/slows with the gem of isolation/solar blessing.

The most misused, and, after he bo and anubis, damage heavy god in the game. He also has incredible utility, making Ra my favorite god to play with. You rarely see a Ra go 15+ and 0 so when you do with this build you'll feel a swelling of pride as your teammates and enemies alike compliment your killing sprees.

For the pure damage build:

Pros:

Extremely fast killing, mitigating any damage from opposing god
High magic power = High amounts of heals making you a great healer
Added damage from your polynomicon allows you to save your ult for sneak attacks, long range damage
Good penetration allowing you to take down magic resist gods
Early mp5, keeps your mana reserves high early for quick farming and leveling early on.

Ra's passive is Speed of light. This passive skill increases Ra's movement speed by 10 percent each time you use an ability, and stacks up to 3 times (or up to a bonus of 30% movement speed). This is an incredibly powerful passive and makes Ra one of the most mobile gods in the game. It is a great passive for hit and runs, and also for escaping. If you find yourself running from and enemy, and have the mana to spare, cast a spell or 2 to take advantage of the added speed to get away. Ra does not have a leap and relies on this passive as his only escape.

I Always start with Celestial Beam. This allows you to hit level 2 the quickest, and then grab solar blessing. Celecstial beam is one of best spells at killing creep waves. Use it while the creeps are charging in, in a straight line and they all will take serious damage, and at around level 3 with this it kills roman ranged in 1 blow. This skill is your primary damage dealer. It has great range, however it moves slowly and will most likely be dodged unless the enemy god doesn't see it coming. For this reason I mainly use this skill at close range, on a slowed opponent. I max this ability first, as it is your primary farming tool/damage dealer. It should also be noted that Celestial beam can also double hit enemies if they are moving away from the celestial beams point of origin, making celestial beam the worst nightmare of a fleeing god.

Next I grab solar blessing. Solar blessing has more utility than any other spell in the game.
Solar Blessing:

Heals Ra along with teammates standing in aoe
Buffs magic and physical damage of Ra and friendly's in aoe
Debuffs enemies magic/physical damage caught in aoe
Damages enemies standing in aoe
With gem of isolation is great at slowing enemies allowing you to catch up and also to do more damage. The slowed enemies are also easy targets for your Searing pain and celestial beam.

I typically don't purchase a HOG with Ra, but I will grab some jungle buffs starting at around level 10. When approaching the jungle I pop Divine light, entering the jungle I cast my solar blessing on the 4 of us in the camp, then when they engage me I cast celestial beam and auto attack the jungle champion to death. This allows for Ra to be in and out of the jungle in the shortest amount of time, taking the least amount of damage. Having 3 stacks of Ra's passive on Ra allowing him to race around the map is an added bonus. The buffs I like to grab for Ra are Cooldown (if I don't already have cooldown reduction, because it doesn't stack), Speed (making Ra even speedier), Protection (always a good buff), Damage (when my Magic power is high to boost it because it buffs you 20%). The Health regen buff and mana buff aren't very useful as Ra already has a heal and should have plenty of mana/mana regen through his items and base stats.

When fighting creeps, celestial beam is your best friend. I cast solar blessing on the melee creeps, to damage/debuff opposing minions while healing/buffing my own, then place Ra in its aoe to buff Ra. While in the aoe I cast my celestial beam through the melee creeps, hitting the roman ranged minions in the back. Then I auto-attack from the aoe until the rest of the minions are dead. Killing minions this way is quick, effective, and it also heals Ra, in case he's taken any damage. Make sure to buy mana pots early, because you will run out of mana early game killing creeps this way. I don't use divine light on minions because it doesn't do enough damage and I like to save it, for its great utility. When really trying to push a lane I will cast Searing pain to make short work of a creep wave, or if an enemy god is dumb enough to stand behind and incoming creep line, thinking he's a safe distance away. Searing pain hits everything in its path so it will not only burn down the creeps, but also hit the enemy god behind them.

Ra is a great lane partner and awesome for team fights. His solar blessing can be used to heal teammates mid battle, or during down time. The buff/debuff can also sway the tides of a fight. He can be used from a distant range in team fights with his solar blessing, celestial beam and searing pain. Typically enemies engaging your melee gods up front wont be focusing on dodging Ra's slow moving celestial beam.