The main use of Lashweed Lurker is clearing permanents that dont die to Kozileks Return: a planeswalker high on loyalty, a creature boosted to 5/6 via +1/+1 counters, or a Hangarback Walker
When the mana is available Deed also finds its way into control decks, giving Oath of Druids players a way out of almost any jam while often leaving their chosen creature intact, and in the old days serving as an unexpected Tutor target that could turn the game around out of nowhere
Of course this isnt really a new mechanic at all, just a reimplementation of the saga mechanic introduced with Dominaria (and later reintroduced with Theros: Beyond Death and Kaldheim)
Investment capital is limited, and the more of it you sock away, the less of it you have for quick flips and other short-term financial moves
With Ashaya, Soul of the Wild, this lets you put a +1/+1 counter on a creature whenever a nontoken creature enters the battlefield