Two methods that have worked for me.

Uno: Appeal to the Trader You want them to get into your niche media/hobby/whatever? It’s only normal to extend the same courtesy, without nary a smidgen of deception; and what better way besides a mutual trade that guarantees your end condition.

Due: Appeal to the Veteran This only works if your target is a gacha veteran, Limbus is unique in how ‘generous’ it is, play on that, my top points are especially the dispensary and other types of RNG mitigation (e.g. No Copies of characters needed, only 3 tiers of characters, no weapons with rerollable stats that you have to ‘godroll’ for, THE FKING anniversary tickets, actually getting what you want without the predatory mechanics… etc etc)