Quick Answer
Guildrun Toxic Contract is a rare item whose official Demo 0.5.5 update increased its base Mana Regen from 4 to 6. The buff makes it a stronger cast-cycle option for a hero who can use Mana Regen and tolerate the contract's trade-offs. The full current item tooltip and exact downside wording are To be confirmed unless checked in the live demo.
Choose Toxic Contract when the hero's next cast or status cycle is the reason the team wins. Do not treat the higher Mana Regen value as a universal upgrade for every holder.
What Changed in 0.5.5
The official patch changed base Mana Regen from 4 to 6. That is the only exact current value this page claims. It is enough to establish the item's searchable update history, but not enough to calculate a guaranteed cast time because other stats, abilities, and conditions affect a run.
The item belongs to the Rare Items section of the official patch notes. Preserve that rarity context, and do not copy a secondary database's full tooltip as if the developer published it. Any missing effect text remains To be confirmed.
Who Wants Toxic Contract
The clearest candidate is a hero whose active ability benefits from more frequent casting or whose scaling uses Mana Regen. Pollen is a useful related example because Demo 0.5.6 directly changes Sanctuary of Bloom's Poison scaling with Mana Regen. Niklas Dealer is another natural comparison because its item creation now occurs every four casts, although the official notes do not say that Toxic Contract is a best-in-slot item for him.
Read the Pollen Fae's Kiss guide and Niklas Dealer guide for those mechanics. The recommendation remains editorial, not official.
Trade-Offs and Item Order
An item can be powerful and still be wrong for the current slot. If Niklas is using Red Hot Deals, item position matters because he can consume the left-most item after surviving combat. Do not place Toxic Contract in a sacrifice position until the team can afford to lose its effect and the permanent value is understood.
The exact persistence of every contract effect is To be confirmed in public first-party material. Use the Niklas hero guide for the established item-order warning and keep the Toxic Contract page focused on Mana Regen and decision timing.
Mana Regen Versus Immediate Stats
Mana Regen is only useful if the holder can cast, survive, and convert the cast into a meaningful result. A hero that dies before its next cast may need Max HP, Defense, or Shields instead. This is why the item should be evaluated against the next encounter, not the number in isolation.
The Guildrun relics guide gives the broader distinction between a run-defining relic and an individual item. Toxic Contract is a targeted item choice; its value depends heavily on holder and role.
Mode Context
In normal progression, the item can help a caster or status route become more consistent. In Red Rift, check whether the Mana Regen arrives early enough to matter before the next boss. In Endless, repeated casts may reward the higher value, but the full scaling and trade-off remain patch-sensitive.
The official notes do not publish a current mode ranking or exact holder list. Those details are To be confirmed. Keep the confirmed 4-to-6 change and the current Demo 0.5.6 scope visible.
Current Verdict
Guildrun Toxic Contract is a stronger Mana Regen item after Demo 0.5.5 increased its base value from 4 to 6. Use it on a holder whose active cycle or status plan can turn Mana Regen into real progress, and verify the complete tooltip before publishing exact drawbacks or best-in-slot claims.