Hi Novice321
it's no bug, I assure you
in your case, Templar wanted to destroy your military fort, so he proceeds in 2 steps
1) he send his main army in full (700k+ troops with siege weapons) to break any troops you might have
2) he keeps 60k troops in reserves, of the same exact type, then click 6x in rapid succession to launch 6 attacks that are meant to arrive shortly after the main attack
it's a perfectly valid tactic.
and potentially quite dangerous if the defending player is online (or the babysitters) : for example, if your army is waiting in the field with the Retreat option activated, you only need to de-activate after the main army has passed, then catch the other 6 that follows
add in a "capitulation", and it should give you time to rebuild the lost level easy
Have fun,