Consider the 20 kilobase TP53 gene named for its massive initially-believed 53 kilodalton protein product (later found to be 43 kilodaltons - see https://en.wikipedia.org/wiki/TP53).
Something that complex and of that length doesn't just "happen" on its own. Considering there are 2^40K unique DNA strings of that length (enumerating every permutation), you could easily spend orders of magnitude more than the age of the universe waiting. Simply put, the odds of randomly generating that are none for all practical purposes.
Also consider apoptosis - where a cell recycles itself when it detects too much damage.
The principle of "survival of the fittest" would intuitively rule out the development of apoptosis - there's no reason for a cell or species to develop that feature on its own because that would damage its ability to replicate. Survival of the fittest would actually encourage cells to proliferate as tumors, because they're preserving their genomes and eating everything else out of existence.
The only logical conclusion is that apoptosis and tumor-prevention was purposefully built-in through intelligent design. There's no way that mutations alone could "figure out" that self-recycling (taking one for the team) would increase fitness. Even if 1 pre-tumor cell in a complex life form suddenly decides to recycle itself, chances are that dozens of other pre-tumor cells disagree (sinking the whole life-form). In the absence of that, the pre-tumor cell that recycles itself never survives to hand that ability on.
Additionally, it's even more implausible for mutations alone to "invent" apoptosis mechanisms and 20 kilobase mutation/damage scanners purpose-built for them.
Then you have cell differentiation. Take for example a simple 2-cell system where both cells are joined together and are specific-purposed for different tasks. If 1 of them cells breaks, the other one can't survive on its own. Obviously, decreasing a cell's survivability wouldn't increase its fitness, considering all the types of disasters and damage that could split the 2-cell system.
From a fitness perspective, you would expect any cell to retain the ability to take over the tasks of a different cell type suddenly found to be in short supply, however that often doesn't happen in more complex life forms. Mammals in particular are notorious for relative inability to regenerate large amounts of damage. The only logical conclusion is that the different cell types were purpose-built (read: intelligently designed) to work that way.
With that mountain of evidence for intelligent design, how do macroevolutionists continue to justify fooling themselves?