The description of Testudo will be updated with a client patch:
When starting combat with a shield equipped you will gain a fading damage absorption shield of up to 100 times your shield level. The absorption shield will dissipate if your first attack is a ranged attack. Fading shields halve in value every 5 seconds.
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Computing the probability that at least one of the following events will occur:
P(a or b ... or z) = 1  P(!a and !b ... and !z)
Probability
