the actions of limit once per turn cards are they per card or just the action itself lets say i have 2 "Rock Lobber" in play can i activate both but only once for each of them ?

Yes. Any action with "Limit once per turn" can be used once per turn, no matter how many other actions of the same kind you have. You can trigger the action of each Rock Lobber you control once per turn.

ah thank you :3 hope to make a good squig deck once Shield of the Gods is out

i was also wondering how "Guard Squigs" worked exactly can it be killed once it turns into a unit since it still counts as a support card

and if so can i put it under the "The Unending Horde" if it leaves play as a unit o.o

Guard Squigs are destroyed through damage, they leave play as a unit, so you technically could put it on The Unending Horde, but you don't want to.

Cards leave play as their current type but enter the discard as their true type. So once the Squigs are under Unending Horde, they are a support again and can't be put back into play with the second half of its effect (which only references units). They still would count as an attached card though, so they would make it more expensive to get your units back from The Unending Horde.

ah very true thank you