Editing Risk (game) (section)

===Attack and defense===
Capturing a territory depends on the number of attacking and defending armies and the associated probabilities.  In a battle to completion, a player who has more armies (even just one more) has a significant advantage, whether on attack or defense (the number of attacking armies does not include the minimum one army that must be left behind in the territory).

Defenders always win ties when dice are rolled. This gives the defending player the advantage in "one-on-one" fights, but the attacker's ability to use more dice offsets this advantage.  It is always advantageous to roll the maximum number of dice, unless an attacker wishes to avoid moving men into a 'dead-end' territory, in which case they may choose to roll fewer than three.  Thus when rolling three dice against two, three against one, or two against one, the attacker has a slight advantage, otherwise the defender has an advantage.

There are online tools available to compute the outcome of whole campaigns (i.e. the attacking of several territories in a row).<ref>{{cite web|url=http://armsrace.plynd.com/probabilities|title=Risk campaign probabilities|access-date=2015-01-13|archive-url=https://web.archive.org/web/20150208181409/http://armsrace.plynd.com/probabilities|archive-date=2015-02-08|url-status=dead}}</ref>

''[[RisiKo!]]'' is a variant of the game released in Italy, in which the defender is allowed to roll up to three dice to defend. This variation dramatically shifts the balance of power towards defense. 
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