TumbleSeed is charming. The basic idea, tilting a level left or right to roll a seed up a level of obstacles, was inspired by Taito's 1983 arcade game "Ice Cold Beer" (also released as "Zeke's Peak"), but here that purely mechanical concept has been thoroughly wrapped up in the pleasant aesthetic of bright colors and solid shapes. The utter whimsy of a seed rolling up a mountain, avoiding obstacles, poking evil creatures, and planting power-ups is also deceptive: bright colors not withstanding, playing TumbleSeed is impossible without mastering its controls.

Interestingly, the game does NOT use motion controls, presumably because the level of difficulty requires such fine motor control already. Your left analog stick controls the left side of the level, your right analog stick controls the right. By raising one side you can make the seed roll towards the other. By lifting or lowering both, you can progress up (or down) the mountain. Some buttons let you open up menus and switch powers, but that's pretty much all there is to it. It's as simple as it sounds, but it seems like finesse and mastery of your rolling seed will be called for, not just mere understanding. I repeatedly failed the first level, but kept coming back for more punishment with a mindset of "No, I think I can roll up a little further this time!"

In addition to avoiding obstacles, you collect crystals on your way up the mountainside. Crystals are the game's currency, required to plant your special power-up seeds in the diamond seed plots littered in each level. One power up earns you more crystals, another earns you more life when planted, still another grants you thorns to surround yourself with that you can use to defeat enemies (who then drop more crystals). A key power-up you'll have is the "flag" seed, which will plant a checkpoint in the level. If you fall down a hole, you only fall down as far as the last checkpoint you planted. You lose more health the further you fall though, so woe to them who forget to plant a flag only to fall so far they lose all their life!

You can also use crystals to buy power-ups at "camps" that exist between the game's levels, or you can "bank" those crystals instead of spending them to earn interest at the next camp. This is a neat aspect to the game: TumbleSeed has injected some adventure/rpg elements into its procedurally-generated "rolly-roguelike" formula. The game may have been inspired by arcade machine novelties, but in TumbleSeed you start in a town, buy power-ups at camp, explore for secret challenges, consider optional challenges and quests from NPCs, and may even come across some huts and characters who pull the curtain back gently on the game's lore and backstory.

One interesting thing I witnessed was an optional challenge where springs were situated on columns above a bottomless pit. Upon touching a spring, the seed would spring upwards on the screen, then float back down. The player's tilting-level would have to be positioned to catch the seed right on another spring, and slowly creep upwards the level section going from spring to spring. If you made it to the end of this section, the game rewarded you with two special seed powers to add to your equipment for that play through.

It's worth noting that the entire game is procedurally generated (even that starting town), so each run has a different layout of holes to avoid, enemies to bypass, secrets to discover, and power-ups to choose between. However, there's also a planned daily challenge mode wherein all players are given the same "seed" value to generate a level with, ensuring that at least for this particular challenge everyone is playing that same level. This is intended to lead to dedicated leaderboards, as well as players comparing tactics for their daily attempts.

The developers shared that they had done 30-40 minute playthroughs of the game, but that they were also doing speedruns, taking risky shortcuts and warps, that could cut that time down to 10 or 12 minutes. TumbleSeed is exciting and unique and very charming, but seems intent on being challenging as well. For some reason, the 80's NES game Marble Madness came to mind as I waited my turn to play TumbleSeed. That was another game that charmed its way into my heart, while at the same time being so challenging that I never beat it.