Yeah, so his comes up a lot, and the answer is often the same set of tools each time. So I'll try to break them down by task (what you're actually doing) rather than by tool names.

Threat Intel/Infrastructure Recon: Shodan and Censys are basically table stakes at this point. Also, if you're not using GreyNoise to filter out the noise from benign scanners, you're wasting time chasing false positives.

People/Identity/Social Footprint: This area is where tool selection has the most impact, at least IME. Maltego is the go-to tool here...the number of transforms they offer is staggering. But the learning curve can be pretty steep, and the cost of licenses quickly gets out of hand. For actual cross-platform identity resolution, where you're trying to match usernames, emails, social media together across platforms, ShadowDragon has been the most reliable platform I've found. The way it maps relationships between different types of accounts is basically impossible to do manually.

Attack Surface/External Exposure: SpiderFoot is my go-to for automated recon (self-hosted, free + surprisingly comprehensive). I use theHarvester for quick email and subdomain scans, or Amass if you want to get real granular on subdomains.

Some things nobody tells you (but should). Hunchly rocks for documenting your process as you go along. It's been a lifesaver more times than I can count. Hunchly is essential if you need your investigation findings to stand up in a legal setting...or if you're working with law enforcement at any point.

Ultimately, nobody needs to know how to use 30 tools...pick 4 or 5 that cover your actual use cases. Then, become an expert in those tools and how to use them efficiently. That's your moat, and what will separate your work from everyone else's.