I found a Scallotooth 
, an Onilad 
, a Naga 
, and a Flaredrake 
today in Lassandal area. But I couldn’t catch any of them!! and I already have a Nilos 
, and I found a second one there, but couldn’t catch it either 
There was no capture option at all, but when it came to normal ones, there was…I’m confused, it happens recently, i don’t know why.
Is this the way it is? or is this some sort of bug, or just me…
btw, those monsters in tower of Deucalion are uncatchable, right???
Probably a monster used summon and it summoned them. Hope this helps
And yes the monsters on the bridge and in the tower are uncatchable, otherwise everyone would have a lot of op arks
if they use summon,the words would appear on screen, right? but there is none. It’s just a normal fight in wild, some are catchable, but some aren’t…maybe it’s just me then :( I’m so sad I can’t catch those…maybe it’s still impossible next time I found them :( weird…
What monsters did you fight before they appeared?
Oh and FYI those guys don’t spawn there.
Sometimes there is a little visual glitch that makes the dialogue box invisible, I think. Gargoyles are practically everywhere, and so are bronzeshells and mantiswords, so it might’ve been one of them.
just those usually appears in Lassandal
maybe ,but there was one fight where ordinary ones were catchable, but when some rare ones appeared, I couldn’t catch them, so pissed, it was in the same fight 
That’s normal isn’t it? There are some fights with regular arks and summoners too.
Next you see them again, attach screenshot & let us know the arks in the battle…