Auntie Mead's Curse of Endless Frogs

You touch a creature, and that creature must succeed on a Constitution saving throw or become cursed for the duration of the spell. When you cast this spell, the target suffers the following

• While cursed, the target rolls a dice at the start of each turn
  
  • If even, no effects
  • If odd, has disadvantage on all rolls until the beginning of their next turn AND roll a second dice
    
    • If even, a neutral frog appears
    • If odd, a hostile giant frog appears and immediately attacks, its initiative will be after the cursed creature's turn

A remove curse spell ends this effect.

At Higher Levels. If you cast this spell using a spell slot of 4th level or higher, the duration is concentration, up to 10 minutes. If you use a spell slot of 5th level or higher, the duration is 8 hours. If you use a spell slot of 7th level or higher, the duration is 24 hours. If you use a 9th level spell slot, the spell lasts until it is dispelled. Using a spell slot of 5th level or higher grants a duration that doesn't require concentration.