The Low threshold for Life, Mana and Energy Shield is now 50% or below (previously below 35%). This means that a single 50% reservation will now put you into a Low state. Light radius has been adjusted accordingly.
The costs and reservations system for skills has been extensively reworked to add new options. Previously, all skills had either a Mana cost or a Mana reservation (with a limited number of effects allowing you to spend different resources instead of Mana). Now, skills can have costs of Mana, Life, Energy Shield, and/or less common resources such as Rage. Most modifiers that previously affected “Mana costs” now just affect “costs”, and will thus apply to all cost values. Modifiers which still specifically refer to “Mana costs” will only modify the amount of Mana a skill costs, not other cost values. Similarly, there are now some modifiers that specifically modify only Life costs. Vaal Skills requiring Souls to use is not a cost, and thus modifiers to costs will not apply to them – this has technically always been the case, but because that distinction did not previously matter, a couple of modifiers referred to this as a cost. Those descriptions have been corrected. Similarly, the base reservation of a skill can now be an amount of Mana or Life, or both (other resources may become Reservable in future), and most modifiers to “Mana reservation” now just affect “reservation” without restriction to either resource. Several mechanics have been adjusted to account for these changes; for example the changes to Blood Magic Support replace Mana costs and reservations with Life costs and reservations, and these changes will now be reflected in the new skill popups.
Percentage reservations are now stored with more precision internally, allowing them to have up to two decimal places in the percentage value, however the total amount of resources reserved must still be a whole number. This prevents some cases where small reductions in reservation values would have no effect due to rounding. As an example, if a skill reserves 50% of Mana, a modifier granting “1% reduced reservation” will now change the reservation to 49.5% Mana, where previously it would still be 50% due to the change not affecting the percentage by a whole number. However, it is still not possible to reserve less than 1 of something, so for a player with 100 Mana, that 49.5% reservation will still reserve 50 of it. For a player with 1000 Mana, 495 would be reserved.
Reserving Mana or Life no longer involves spending anything – so you don’t need any current Mana to turn on an Aura, you just need enough of your Mana orb to be unreserved that the Aura’s reservation will fit. However, while previously reservations were mutually exclusive with costs, this is no longer the case and it’s possible for a skill to have both a reservation and a cost, in which case the cost will still require spending (but using a reservation skill a second time to ‘turn it off’ does not require paying the cost again). The most notable case of this is Mine skills – these all have costs as well as reservations, which must both be satisfied to use the skill, and can each be modified separately. This also means that mechanics that add to the costs of skills, such as the Voidbringerunique gloves, will now affect skills with reservations, which previously escaped this due to being unable to have both. Likewise, Support gems that add a Mana reservation to skills, such as Blasphemy, no longer inherently remove the cost as part of that process.
The stats which limit the total rate of recovery per second from leech have been changed. Previously these limited any recovery based on what kind of leech it came from, but they now limit recovery from any leech based on what kind of recovery it is. This has no effect except in cases where one kind of leech applies a different kind of recovery. For example, the keystone Immortal Ambition makes life leech cause energy shield recovery instead of life recovery. Previously this was limited by ‘Maximum total Recovery per second from Life Leech’. That recovery will now be limited by ‘Maximum total Energy Shield Recovery from Leech’.
Modifiers that allow your Hexes to affect Hexproof Enemies (such as the Cospri’s Willunique Body Armour) no longer allow your Hexes to affect yourself while you have Hexproof (as you are not your own Enemy).
The Corrupted Blood debuff has been updated. It now has a maximum stack size of 10 and is now consistently treated as being completely separate from Bleeding. Various Bleeding-specific modifiers that may have previously applied to Corrupted Blood will no longer apply. Modifiers that affect both Bleeding and Corrupted Blood such as the “of Staunching” modifier on Flasks have had their descriptions updated to reflect this change. Monsters that apply Corrupted Blood have been balanced around these changes accordingly. Corrupted Blood applied by Monster modifiers now have different values, and these values are now calculated based on the Monster’s level rather than its main hand damage, so some effects which raised Monster attack damage no longer scale Corrupted Blood in unintuitive ways.