Hitting any mob for 0 damage increases the action count in stat screen. Tested with physical immune, that spider and regular 0 hits.
version 1.30.5 (yesterday)
Also the descriptions for any tank ability are still wrong. They should say "charges with damage taken" instead of "charges with hits taken". These abilities don't charge if you take a hit with zero damage, so it is highly misleading and it is stated correcltyin the portal page.
https://dictionary.cambridge.org/dictionary/english/hitI know that the last thing is nitpicky, but it is only a text change and it better reflect the actual function of those abilities - unless you want to change them to charge with 0 hits aswell