Luck

Some components are designed to offer small chances of catching a mouse regardless of the mouse’s strength. It is not uncommon for lucky traps to grant hunters the ability to catch mice that seem far too powerful for their trap.

Luck is a trap attribute that gives the player a chance of catching a mouse even if it would have normally gotten away. It works independently from the power and power type of a trap. Luck does not affect the attraction of mice, but as of April 2009, it also has a small effect on loot dropped by mice. Additionally, hunters who complete special offers or donate for SUPER|brie+ receive an additional 7 luck added to their trap's luck and a gold shield on their Hunter's Profile page for 30 days or more.

Details of luck

The Developers mentioned (around the 14 minute mark in a video from 13 March 2009)^[1][2] that luck is nonlinear, so the more luck you have, the more effective it becomes. Hence 8 luck is more than twice as good as 4 luck. Moreover, they also mentioned that it is more effective against a stronger mouse than against a weaker mouse, so 4 luck against a stronger mouse has more benefit than 4 luck against a weaker mouse. Luck works almost like a separate roll (see Hunting Sequence), so that regardless of a trap's power and power type attributes, a mouse can be caught based on pure luck.

The Developers also mentioned that 7 luck bonus "equates vaguely to approximately having one less failure to catch a day."

Trap setups

The five weapons with the highest luck are the limited edition DeathBot (Chrome Edition), Snow Barrage, PartyBot, HitGrab Rockin' Horse, and HitGrab Rainbow Rockin' Horse with 30, 28, and 25 Luck for the last 3 weapons respectively. The weapon with the highest luck that is not limited edition and currently available to players is the Arcane Capturing Rod Of Never Yielding Mystery, with 18 Luck.

The base with the highest luck is the limited edition Magma Base, having 10 luck, followed by the Aqua Base with 8 luck. Thus the highest possible luck value in-game is 47 Luck, pairing the DeathBot Chrome with the Aqua Base and the golden donor's shield.

Strategy

The Developers mentioned that luck is the least important trap attribute broadly speaking, and because power works much more often than luck does, hunters should generally not neglect significant differences in power or power type in favor of boosting luck. However, there are exceptions.

The PartyBot, for instance, is a generally effective trap for the Mousoleum, partly because of its luck, even though many of the mice there don't match its power type^[3]. Before the Ancient Box Trap was introduced, it was necessary to set up a trap with the highest luck when hunting the Acolyte Mouse, since there was no trap that matches its power type and it was so difficult, thus luck was the only tool available. Without a Forgotten type weapon, if the hunter is specifically trying to catch an Acolyte, the hunter can maximize his or her odds by using the luckiest trap setup available, though it may come with a lot of misses on the Forgotten Mice that also dwell in the Acolyte Realm if that trap is not of the Arcane power type.