Guild Wars 2

So is it true the new pets in HOT can only be had by triggering and completing events?

The HoT pets are gated through their specific map locations based on the current Meta event progress, so yes. I believe Bristleback is an expection though.

I remember that the tiger was locked behind a vine wall section of dragon’s stand, which could only be opened by completing the meta event. I think since then the vine wall has been removed and the tiger can be reached without completing the meta event now.

I don’t know about the other pets though. Check wiki?

BB is open to pick up when walking past, I saw 2 yesterday.
Tiger and Electric Wycern have both been moved and are more accessible now, just find a DS map that’s recently complete and go pick them both up.
Smokescale is behind an event chain but a map close to the end of that chain will have them open.
Fire Wyvern, during the night event in VB glide down if I remember correctly, it’s been a while.

You don’t even have to glide down, you can climb the vines to the Fire Wyvern location from the South-eastern WP, check the the wiki for details.