Badge System

Taken from Paper Mario but also present in some other RPGs (sometimes under a different name), a badge is a special type of item that a character can equip (or "wear") in order to gain some kind of handy effect, but unlike equipping weapons or armor, many badges can be worn at the same time. In Paper Mario, the factor that limited the number of badges that Mario could wear was a stat called BP (Badge Points). Arpeggio was originally designed without badges out of a desire to avoid restricting players to content predesigned by the Maestro, and so the BP stat is absent. However, badge implementation was later made possible, though it technically remains an optional add-on to the system. As such, alternate ways of handling badges can be substituted, but here I'll explain my particular take.

A given badge will list a BP value, and in order to wear the badge, this value must be extracted from the character's maximum HP, VP, or MP. This would allow, for example, a character who knows no magical attacks to effectively use their pool of MP as BP instead (or vice versa, a magic user to use their VP). So then, if a badge costs 3 BP, and a wearer with 20 MP puts it on and selects MP as the stat from which to extract, then this character would be treated as having a maximum of 17 MP, but if the badge is unequipped, the 3 points are restored, bringing the maximum back up to 20. (It would probably be best to then leave it as 17/20 in order to avoid exploitative healing.) Naturally, BP tolls cannot reduce a character's max HP below 1, though VP and/or MP could be reduced to zero. A single badge cannot split its BP cost between different pools, but each badge equipped can draw from a different pool, making a character's effective total BP equal to (max HP - 1) + max VP + max MP. Of course, if VP and MP are at zero, no attacks that require them can be used, and reducing HP isn't great either, so there's a balancing effect.

Player characters generally cannot have 0 max VP or MP without wearing any badges, but the same is not true of enemies, who often have no VP or MP if they have no attacks that can utilize them. Because of this, a special rule exists that a character with a natural maximum of 0 in either VP or MP is allowed to wear one badge of any BP cost for free, and characters with 0s in both VP and MP can wear two free badges. After such a character puts on this number of badges, any additional badges worn follow normal BP extraction rules for that character. This rule can technically apply to a player character who has 0 max VP or MP (a special condition known, fittingly, as Zero Maxing), but mainly exists to allow Paper Mario enemies (who generally have low HP, VP, and MP, and therefore not much BP) to be able to wear badges, so a Maestro might choose not to extend the privelege to a Zero Maxing player, who is more likely to abuse it.

If HP is used for BP extraction, a character's Danger Zone ignores this, still using their actual full maximum HP to determine its range. As such, BP extraction from HP can leave a character constantly in the Danger Zone, meaning that any special effects that occur when that character is in Danger are always present. This includes Danger Zone effects granted by badges.

When not worn, a badge takes up a slot in a character's item inventory just like any other item. However, once put on, a badge no longer takes up a slot, meaning that there is no limit to how many badges a character can wear so long as BP requirements are met. However, if a stealing ability targets badges, it can target ones that are currently equipped, and if these are successfully stolen, the character loses their effects immediately. Similarly, during mid-battle, a character may use their turn to rearrange their currently equipped badges, and following this the effects change immediately mid-battle. Sometimes the specifics of gaining and losing effects this way will leave the Maestro scratching their head, but work it out as best you can; as already noted, stats reduced by BP extraction are not restored upon taking the badge off, even though the maximum is increased, so this may discourage such mid-battle badge tweaking. Outside of battle, of course, badges may be switched around as much as the character likes, but the majority of badge effects are only relevant to battle rather than the field. Regardless of what the effect is, on the character's sheet, "{Badge}" will be placed in front of it to indicate that it is being granted by a badge, and the whole will of course be removed if the badge is. Feel free not to bother adding and removing descriptions of badge effects to character sheets if you can remember them yourself, but generally at least special attacks granted by badges should be copied onto the sheet.

The effects of some badges are enhanced or altered by wearing more than one copy of the same badge. Such things will be explained in each badge item's description, and if no such effect is indicated, then no such effect exists for that particular badge. Badge effects can be just about anything.

Vehicles, even if they are sentient, cannot wear badges. To create a conceptual reason for this, I might say that badges, rather than merely being pinned to clothing, actually pierce the wearer's skin when worn, explaining why their HP, VP, or MP actually drops, and that the trade-off between this and the badge's effect is something like a temporary blood pact, with whatever magic or whatnot by which this works refusing to make the deal with a not-quite-living object. This could create problems with robotic player characters, though, so justify it however you like.