Chainlife NFTs mature on-chain as they're transferred between addresses and when an owner 'shifts' their token.
Transfers and shifts (positive and negative) are tracked on-chain, and together these determine the token's World Level. New looks, features, and functions unlock at both hard-coded and hash-controlled World Levels. An owner sending their NFT to themselves will iterate the transfer count, but there's a better way.
Owners can buy level shifts for a very small amount - 0.001 per level. By using the smart contract's SHIFT_LEVEL function, an owner can shift a token up or down a couple levels, or dozens, hundreds, or even thousands of levels at once. Note that these are additive, so if a token is already shifted by X, and you shift by Y, it's now shifted by X + Y.
Shifts mature the token just like a transfer, but transfers do something shifts do not; they change the token's starting seed - the population of live cells the token begins with. Chainlife NFT's use the owner addresses of both sender and receiver to calculate the starting seed. In this way, each NFT can change every time it is transferred.
Due to this unique feature, a preview function is embedded in every Chainlife, allowing owners/potential-buyers to see the next starting seed if the token was transferred to the specified wallet. For those not familiar with cellular automata, this is useful as it can allow the crafting of the starting seed to produce desired patterns.
Once a Chainlife token reaches a threshold when most feature unlocks have occured, it shows a partial border when paused. This partial border communicates that it has unlocked a new function; the Custom Rule preview. After a Chainlife completes its primary maturation (16 levels), a full border appears around the image in its paused state. Fully matured Chainlife NFTs allow the use of on-chain custom rulesets. For those not familiar with cellular automata, this is one of the most exciting features!
The most important takeaways from all this: transfers will always affect a Chainlife NFT, at minimum the starting seed, making each Chainlife NFT permanently customizable. With the ability to quickly shift a token to a new level, collectors interested in the features of the token don't have to trade or transfer their token in order to mature it. Shifts are additive, inexpensive, and are intended to offer owners a non-destructive way to enjoy their token.