Ok, friend... let me help you fix this up ok?
Your lead is nothing short of terrible. Beedrill has poor defenses, poor speed and poor everything. He'll maybe get one layer of spikes down before you're dead. That being said I would like to suggest Jirachi as a lead:
@ Choice Scarf
Timid Nature
176 Spe / 252 Atk / 80 HP
- Iron Head
- Zen Headbut
- Ice Punch
- Thunder Punch
THis is your new Anti-Lead. He counters the majority of the leads today, besides metagross and heatran, and then comes back in mid to late game to become a powerful revenge killer. He can come in a on Salamence or Gyarados after a Dragon Dance and kill them with Ice Punch or Thunder Punch respsctivly. Iron Head and Zen Headbut are both there for STAB and provide flinch 60% of the time. This helps you out early game as then you don't have to worry about switching causing you damage thanks to Stealth Rocks.
Forretress can stay as a pokemon, but his mvoeset should be changed a little. Toxic Spikes isn't as powerful as it used to be, with most of the powerful sweepers being immune to it, and getting absorbed if a posion pokemon comes in, it will require a lot of time and effort to set up. Instead I would like to suggest:
@ Shed Shell
Relaxed Nature
252 / 162 Def / 92 Atk
- Spikes
- Toxic
- Explosion
- Rapid Spin
This isn't advanced generation anymore, you'll need to start buffing Forretress's defense if you want him to be a wall like he used to be. The set is simple, you come in on something you resist, then use Spikes. You won't be scared of Magnezone switching in because you're carrying Shed Shell which allows you to switch out if Magnezone comes in. Rapid Spin is for getting rid of rocks/spikes if your opponent gets them set up. Gyro Ball is for STAB, and Explosion, of course is for when Forretress can't do his job anymore. This still allows for you to get residual damage up, but hurt many pokemon, like Metagross and Lucario. I added Toxic Spikes in so it makes your stall easier. As it does hit some pokemon (like Machamp) who are common in OU
As for Gastrodon he does a decent job, but I would like to suggest my old friend Swampert in his place.
@ Leftovers
Relaxed Nature
240 HP / 216 Def / 52 Atk
- Ice Punch
- Waterfall
- Earthquake
- Stealth Rocks
This set is superior to your gastrodon set in two ways. Swampert can threaten pokemon like Tyranitar and Heatran by coming in and using STAB Earthquake. Also Swampert gets Stealth Rocks down. Something that will hurt your opponents Flying types that aren't effected by Spikes. Ice Punch is to hurt Zapdos whos Thunderbolt you can come in on and Waterfall is for everything that Ice Punch and Earthquake won't hit, mainly Bronzong and Skarmory. The one downfall Swampert has over Gastrodon is no recover, though you can replace Ice Punch for Rest if you really want to.
Maganium was the only Grass type pokemon I never liked, she doesn't have that great of stats and her movepool has some potential, but not enough that it makes up for her stats. Your team lacks a Special Wall, and for that I'd like to suggest this Blissey:
@ Leftovers
Calm Nature
200 HP / 176 SpDef / 80 SpAtk
- Wish
- Protect
- Flamethrower
- Toxic
This is a very potent special wall, she can take most hits and shrug them off. 200 HP EV's is so she can reach 700 HP, 176 SpDef EV's is to make her extra bulky and the rest is mainly to boost Flamethrower. This set helps keep your other pokemon alive by using Wish, Protect helps Blissey heal herself, and Flamethrwer is to hit Scizor who LOVES to come in on you. Toxic is to hit Flying pokemon like Zapdos and Salamence with it. This pokemon will help hold your team together.
Drifblim is outclassed bymany of the other ghosts, namely Spiritomb and Rotom. There are reasons to use both, but Roto comes with a buch of weakness that Spiritomb wouldn't have to worry about. While Rotom generally has better stats and moves that Spiritomb. Spiritomb is geberall the better suggestion on a stall team since he is still extremely bulky, can pose a threat to Tyranitar and generally. While Roto must fear Tyranitars STAB Crunch and Pursuit while not being able to harm it much any way (unless it's Wash Rotom).
@ Leftovers
EVs: 252 HP / 100 Def / 156 SpD
Calm nature (+SpD, -Atk)
- Shadow Ball
- Rest
- Sleep Talk
- Hidden Power Fighting
This guy will be another answer to Tyranitar (somewhat) and is also a Gjost, meaing Rapid Spin is useless on him. He can also be considered a Status Absorber thanks to Rest and Sleep talk. Shadow ball + Fighting is a compeltely unresisted type conbination and will hit most anything. The only problem is that it also hits very little for Super Effective Damage. Spiritomb is more on the SpDefensive side to take Gengars SpAtk, but also has def EV's to allow him to take some Physical attacks.
The last thing your team needs is a good Earthquake resists. I have a good suggestion over Armaldo as well to help you
@ Leftovers
EVs: 252 HP / 216 Def / 8 SpD / 32 Spe
Bold nature (+Def, -Atk)
- Recover
- Perish Song
- Grass Knot
- U-turn
This Celebi will hurt Stat Uppers like Suicune by making them not being able to keep their Stat Ups for longer than three turns thanks to Perish Song. As it makes them fait after that amount of time. Recover is used to keep Celebi alive as much as possible, and Grass Knot is a good STAB move. Using U-Turn is amazing in a stall team as it allows you to get to the correct stall pokemon after seeing what your opponent switches to. The EV's make Celebi be able to take boosted attacks from Gyarados, among many others, and maybe the occasionaly Special Attack.
Hope I helped,
Empoleon
