Klauth, Unrivaled Ancient is made for Raggadragga. Also, Selvala, Heart of the Wilds, Kami of Whispered Hopes, and Cradle Clearcutter are nice like Heronblade and Marwyn.

It's those scalable interactions I'm focusing on in Raggadragga Mana Saga deck, and I just realized that Wurmcalling goes infinite with those mana dorks! Now, to find something I can cut...

Ah, yes, I should qualify it in a couple of ways. First, I don't have a group to play with, I have one friend who mostly builds Tier 4 decks, and I have to tailor mine to be strong in the 1v1 matchup. Second, we both are cool with proxies; I don't have all these cards but I do have a laser printer. ;)

I see the benefit of the going wide in the attack with Sylvan Awakening - I have Liege of the Tangle in the Maybeboard for similar ideas, and I think if I ended up playing multiplayer, I would make a shift like this.

Similarly with Kozilek, right off the bat, the "two target players" is diminished in my circumstance, but again, I see the go-wide strategy as strong in the multiplayer. I playtested your deck, and I was impressed at the (colorless) mana available quite early, it rivalled the heavy mana-dork ratio in my own deck!

Nice deck, I have a Raggadragga deck as well!

I have found that Last March of the Ents and Nissa's Revelation are extremely good when you have Ragga and a scalable mana dork like Marwyn out. Especially Last March, as it can look at the mana dork's recently +7 toughness and draw cards off that. Then you hit a couple of 7+CMC cards and combo off, ending with a +28/+28 mana dork with trample and a battlefield of beauties!

Raggadragga Mana Saga if you'd like to check mine out. I'm focused on the ideal mana dorks, and comboing up 7CMC cards with scalable dorks like Heronblade Elite, along with card draw (like Regal Force) and the baddest threats.

I have a Raggadragga deck as well, just out here looking for ways to tighten it up! What do you think are your strongest cards/combos?

Raggadragga Mana Saga if you'd like to check mine out. I'm focused on the ideal mana dorks, and comboing up 7CMC cards with scalable dorks like Heronblade Elite, along with card draw (like Regal Force). I find it goes off very reliably, ending up with a turn 5 battlefield with Summon: Bahamut, Klauth, Unrivaled Ancient, and Blightsteel Colossus all lined up... or worse!