As of 2022-03-04T20:58:58.442Z, checking all subdomains of https://mod.land/ via the following script:

import CNAMES from 'https://raw.githubusercontent.com/denosaurs/mod.land/master/cnames.ts'

const domains = Object.keys(CNAMES).filter(CNAME => CNAME !== '@').map(CNAME => `${CNAME}.mod.land`)

for (const domain of domains) {
    Deno.stdout.writeSync(new TextEncoder().encode(`Checking ${domain}... `))

    try {
        const res = await fetch(`https://${domain}/`, {
            redirect: 'manual',
        })

        if (res.status === 200) {
            console.log('OK')
            continue
        }

        const meta: Record<string, unknown> = {
            status: res.status,
        }

        if (res.status > 300 && res.status < 399)
            meta.location = res.headers.get('location')

        console.error(meta)
    } catch (e) {
        console.error(e)
    }
}

Checking adons.mod.land... { status: 404 }
Checking atordvairn.mod.land... { status: 404 }
Checking autopilot.mod.land... OK
Checking crewdevio.mod.land... OK
Checking denodoc.mod.land... Sending fatal alert BadCertificate
TypeError: error sending request for url (https://denodoc.mod.land/): error trying to connect: invalid peer certificate contents: invalid peer certificate: CertNotValidForName
    at async mainFetch (deno:ext/fetch/26_fetch.js:280:14)
Checking denopack.mod.land... OK
Checking dext.mod.land... OK
Checking discordbot.mod.land... OK
Checking discorddn.mod.land... OK
Checking discordeno.mod.land... OK
Checking dyno.mod.land... { status: 404 }
Checking gamer.mod.land... OK
Checking ghaerdi.mod.land... OK
Checking god.mod.land... { status: 404 }
Checking godwhite.mod.land... { status: 404 }
Checking harmony.mod.land... OK
Checking harmony-korean.mod.land... { status: 404 }
Checking imlshorid.mod.land... OK
Checking keyv.mod.land... OK
Checking natico.mod.land... OK
Checking range.mod.land... OK
Checking shyngys.mod.land... OK
Checking slashdeno.mod.land... OK
Checking suzumi.mod.land... { status: 301, location: "https://suzumi.mod.land/" }
Checking the-all-javascript-blog.mod.land... { status: 404 }
Checking thebigbot.mod.land... OK
Checking usbo.mod.land... OK
Checking x.mod.land... { status: 307, location: "https://x.mod.land/" }

Probably worth removing old domains with 404 status and remind owners of domains with 3xx status.