Bug: Haste instantly causes lethargic

[Martin]

Within the same turn. Cast Haste, next spell instantly lethargic. I mean ffs it's one of the most basic spells and you can't even get it to work properly. Potion of Speed works fine..

[Haven]

If the next spell requires concentration, it will immediately end haste and trigger the lethargy. What spell were you casting? I'd maybe recommend a Potion of Speed as a solution