Ultra-growth potion

An ultra-growth potion or Malignius Mortifer's Super-Ultra-Flora-Growth potion is a potion created by Malignus Mortifer, a necromancer currently living near the roads south of Falador. The potion was purchased by Wyson the gardener to make the plants in Falador Park sizable enough to resist destruction by the moles living there. However, as a side effect, one of the moles grew hugely in size after eating plants protected by the solution, resulting in its dubbing as the "giant mole".

A single dose of it can be obtained as a drop from the Giant mole in hard mode, and as with any potion, up to four doses of it can be combined into a single vial. However, it cannot be combined into a flask, unlike other potions. It can be used on healthy fruit/wood trees to skip their growth ahead 2 stages. This can be done only once per tree; using multiple ultra-growth potions will have no effect.

The potion has no effect on spirit and elder trees. Attempting to use it on one will make it display a message reading "The potion isn't entirely safe. You don't want to risk it reacting with the magic of the spirit/elder tree."