As a fun one-off that might turn into a campaign, I'm planning on running a Godzilla-inspired Kaiju game. At the moment, I have stats for each Kaiju race available to the players, a collection of "monster traits" (breath weapon, flight, amphibious, claws, ect) the players can buy with starting XP, in addition to raising attributes, and a set of Kaiju-specific skills. However, I want to include Kaiju Weaknesses, an optional mechanic to gain extra starting XP in exchange for accepting some form of handicap. For a few examples:
Elemental Weakness (5XP) - The player selects an element (fire, electricity, ect.). Attacks of that element add one boost die, and a successful attack adds 2 damage per Success instead of 1.
Frail (20XP) - Halve the Kaiju's Wound Threshold.
Vulnerable (25 XP) - The Kaiju's soak is in Vehicle Scale instead of Kaiju Scale. (Personal scale=1, Vehicle scale=10, Kaiju scale=50). Furthermore, the Kaiju's Wound Threshold is converted from Kaiju Scale to Vehicle Scale. (A 12 KS would go to a 60 VS, for example. This way the Kaiju still takes damage from Vehicle scale weapons that wouldn't get a full point of Kaiju scale damage past soak.)
Ponderous (15XP) - The Kaiju may not use its free maneuver each turn to perform the Move maneuver. (Can still use its action or suffer 2 strain to perform the Move maneuver.)
These are what I have for Kaiju weakness options so far. Any suggestions for more would be greatly appreciated!