Commander Legends

Commander Legends brings a lot of potential for Cubelet. Cubelet is largely a multiplayer format. When looking at what makes a multiplayer format good, there is a lot of crossover between it and Commander. The two mechanics that seem to be standouts are Encore and Monarch. When designing your cubelet, these two could be dramatic focuses/themes of the cubelet or could be a splash mechanic in your overall construction.

One thing to note: there are a group of cards that reference if you control your commander, which definitely does not apply to this format, so they would be evaluated as if you didn't control your commander.

Vow Cycle
Interesting cycle of cards that can be political tools. Generally speaking, they are fine and you will probably want to have access to all of them or none of them.

Court of Grace
When you are not the monarch, this card seems fine. When you are the monarch, this card seems absurd without some sort of way to balance it.

Court of Cunning
Not ideal for this format due to shared library.

Fall from Favor
Powerful effect and an easy way to introduce Monarch into your game.

Court of Ambition
Might be too powerful, but worth a test.

Exquisite Huntmaster
The first time, it is basically a different kind of Flametongue Kavu, but gets interesting when you are able to cast it for Encore.

Court of Ire
Very powerful. Essentially a removal spell or a quick way to eliminate a player if you are the monarch.

Krark, the Thumbless
Adds a level of chaos to the game as long as it sticks around.

Toggo, Goblin Weaponsmith
Because you control your land drops, you control how important rocks are to you,

Wheel of Misfortune
Interesting mini-game to play with the group. Might be fun to have in the deck for the first few plays, then look to swap it out or always make it a land.

Court of Bounty
Fundamentally does not work as your hand won't have lands in your hand when you aren't the monarch. This could mean that the card is fine since you can really only do something when you are the monarch.

Halana, Kessig Ranger
Having the ability to pay to have your creatures bite other creatures is unique and could be fun.

Araumi of the Dead Tide
Worth testing, might be too powerful. Just the kind of card you look for in Cubelet.

Belbe, Corrupted Observer
Everyone is hungry for mana, so this might actually stick around for a turn or two.

Gor Muldrak, Amphinologist
Just the right level of crazy/interesting for Cubelet