Yeah but keeping 15 people inside a Counter Spell bubble in GvG is already a bad idea right off the bat. You’re making it easy for others to focus their AoE in your team and stuff like Raise won’t be blocked by Counter Spell since it only blocks rank 1 debuffs. Also, since it doesn’t make you completely immune to damage, anyone in the other team can use a AoE physical skill and obliterate your 15 guild members easily (since they’re all grouped together).
Oh yeah, and let’s not start with the “you need to stack AoE Defense” talk. Some skills ignore AoE attack/defense mechanic and Counter Spell is simply far from the best defensive skill in the game. Needing something like AoE defense to make Counter Spell more useful for bigger groups already means Counter Spell is flawed by design. Having something like Ausrine or Sterea Trofh instead is so much more reliable in so many ways.
Keeping somewhere around 5 people inside the bubble is much more practical, and for that, you don’t really need anything past lv 5 Counter Spell.
Only counts if the trap skill has a hp bar. Stuff like Diev statues do count towards the limit but heal tiles don’t.