(edited by shanrak.1430)
Slayer counter for Giants doesn't move.
Yes, only a few count as ‘Giants’ for the Slayer Achievement.
http://wiki.guildwars2.com/wiki/Giant
Good luck.
Thanks. Will do.
If only risen giants counted as giants instead of risen.
need more giants, please.
We might be small and outmanned, but we have big tomatoes.
Note that if you do want to farm them, the only real event available for doing so is http://wiki.guildwars2.com/wiki/Help_U.N.I.T._find_and_destroy_the_Inquest. Even still, it’ll take you a very, very, very, very, very long time to farm all the giants you need, so be prepared to put fun aside if you decide to go for it.
As someone that has participated in the “Broken Golem” event (and finished Giant Slayer), I can say the following.
It helps if you can get an extended group of people on your friend list that want to slay giants.
If someone wants to complete the event be courteous with them.
If you see new people near you while doing the Broken Golem event, inform them that you are slaying giants and ask them if they want to join too. (More people = more giants.)
You can work on other slayer titles while waiting for the Broken Golem event to respawn.
You can work on some of the dailies while waiting for the Broken Golem event to respawn.
Good luck.