Animar or Riku all depends

Riku would have you a balance instants and sorceries + creatures

while Animar will be more about counter generation and creatures and less about instant and sorceries

you should totally put in Elvish Piper , Quicksilver Amulet and Tooth and Nail . Ways to cheat in your creatures for cheap is the best way to get riku going.

oh wait, you already have the piper never mind =D

@10vernothin

Tooth and Nail 's in the maybeboard, I only remembered it after I built the deck and anyway I don't have it so I'll switch it in when I do. Quicksilver Amulet might be a bit too slow, assuming I played it on turn 4 I should be able to cast something anyway next turn with 5 mana. I could probably drop something slightly above the curve with it, but I don't think that matters so much in commander. Or am I wrong?

oh no, I'm just abusing the fact that you don't need to cast it for you to work with riku's triggered ability, so why waste all the mana you can be using to copy to cast the creature?

Speaking of triggered ability, you should put in Strionic Resonator . 2UR to copy an instant/sorcery spell second time is not bad and you can use 2 to copy an ETB trigger or 2UG if you want the trigger AND the creature

@10vernothin

that's true, I'd get to copy creatures earlier. it's going in the maybeboard for now :)

Strionic Resonator 's already in maybeboard btw :P

My maybeboard's gonna be longer than my main soon...

Based on the main, this is basically just a "Super Powerful ETBs" deck. If this is indeed the case, many of the cards you're considering are just not synergistic enough to be worth including. Specifically, I wouldn't worry much about AEtherling , Diplomatic Immunity , Dissipation Field , Forbidden Orchard , Hull Breach , Jace, the Mind Sculptor , Parallel Lives , or Thran Dynamo . There are maybe arguments for Orchard or Dynamo or Parallel Lives, but the rest just don't do much for you.

Also, I find it kind of odd that you're running Archaeomancer but not Izzet Chronarch . You might also consider the spell Turnabout just because it's absolutely bonkers to copy.

Cloudstone Curio is good for casting 2 or 3 cards multiple times in the same turn (Animar just needs a few counters to start off and then you need a couple creatures with only 1 point of colored mana to cast). Morph creatures get ridiculous (you can go infinite with just 2 if you want to). One of my favorite combos casts Avalanche Riders until I run out of red mana, coupled with almost any green or blue creatures.