Monk Mantra descriptions say "Only one Mantra can be active at a single time".
But if we build a party with more than one monk:
Is it possible get the effect of more Mantras?
If two monks use the same Mantra, do their effects stack?
If two monks use the same mantra with different strengths, does the strongest one always take precedence?
Does the 3-second on-cast effect of the same Mantras stack?
Do rune-effects of same-mantas stack?