It's an interesting strategy but unfortunately it's only work in low ladder. FEAR surprise people who dont know how it works but once you face people who understand how to deal with that, your fear mon will be more like a deadweight than an useful help against the opponent's team. You can still play that to have fun in laddering but it's not really a competitive strat.Ok so idk if FEAR is considered uncompetitive, but I've been playing ZU since it was OMotM and I'd had moderate success with FEAR Sub-Seeder Cottonee. (Not a full FEAR team, but one FEAR mon can catch your opponent off-guard and Cottonee can chip away at potential threats with relative ease) However, due to the prominence of Liepard and Torterra (Liepard being immune to Prankster and Tort to Leech Seed) it was sometimes too much of a dead-weight.
However, with these mons gone and the highest ranked Grass type mon being Tangela (lol), Cottonee has seen much greater success lately.
Ok so the strat is pretty self-explanatory but I'll explain it a little because the set is optimised for almost any situation provided hazards are gone and you can switch Cottonee in.
So let's assume for argument's sake your opponent has no Grass or Dark types on their team, then the easiest option is to lead with Cottonee. This circumvents the issue of hazards potentially getting in the way.
Anyway, when Cottonee switches in, beit on turn 1, 2 or 85, it's first play will always be leech seed. Then, its second play is always sub. If the opponent switches out, you are behind a sub and can leech seed their switched in mon the next turn. In this way you will ALWAYS get Sub-Seed up. (SR support is helpful, to discourage frivilous switching, but not necessary as switching doesn't break the strat. Plus, Endeavour is a thing.)
Because Cottonee is level 1 leech seed will always restore it back to full. From here you spam Sub until the opponent does something other than attack. (Either that or they switch out or faint: simple as that.)
Only when you have Leech Seed AND Substitute up can you use either Endeavour or Encore.
Say you are in this optimal position and your opponent goes for an SD. Then you encore next turn. Simple.
Alternatively you can Endeavour them, (and generally Endeavour is less situational than Encore) but there is a pit fall here that I myself have fallen for before. If you Endeavour (bringing them down to like, 2%) and then they break your Sub/you Endeavour without Subs up, then Leech Seed will only restore what ever tiny portion of their health is left, ie: it will not bring you back to full so that's something to watch out for.
I don't have any replays atm, but if anyone is interested then I can jump on the ladder. (Edit: Jump on the ladder to get some replays)
Have fun playing the tier !