I've been playing the Battle Tower for about half a year now. Rather, I   should say that the Tower's been playing me. Six months of Brightpowder   misses, Ice Beam freezes, and Focus Band activations does a lot for   one's patience. Jumpman and Peterko must be saints by now. Still, I have   experienced more pleasure than frustration in this endeavor. As such, I   would like to continue.
First, however, I need to establish how to continue by recognizing my   mistakes. One of the goals with which I constructed my first team was speed, for practicality's sake.  Twenty-one   turns of Acupressure seems like it would take a while. Additionally,   spending less time on individual streaks means that I can feasibly   attempt more, allowing me to learn faster. As I go for longer streaks, I   think I'll let this one slide, but it's been useful for me. After more   analyzing and theorizing than I care to admit (yet still not enough), I   came up with the following combination:
Dusknoir (FRAUD) @ Choice Scarf
Male, Bold, Pressure
252 HP / 116 Defense / 116 Special Defense / 20 Speed
152 / 120 / 187 / 76 / 170 / 68
Trick / Grudge / Disable / Protect
Scizor (FISKARS) @ Iron Plate
Male, Adamant, Technician
94 HP / 252 Attack / 164 Speed
157 / 182 / 120 / 75 / 100 / 106
Bullet Punch / Superpower / Substitute / Swords Dance
Heatran (GOBLIN) @ Leftovers
Female, Modest, Flash Fire
188 HP / 252 SpAtk / 68 Speed
190 / 99 / 126 / 200 / 126 / 106
Flamethrower / Earth Power / Hidden Power Electric / Substitute
Hopefully you can follow my train of thought.  Trick and Grudge  leave  the opposing Pokemon locked into a move with no PP.  In this way,   Dusknoir allows Scizor three to five turns of setup.  Given this time,   Scizor can boost enough to threaten 95% of the Battle Tower with OHKOs.    Heatran rounds out the team, taking down leads Dusknoir can't handle,   and absorbing fire attacks aimed at Scizor.
While it is  unorthodox, there are advantages to such a strategy.  The  usefulness of  Grudge is in its ability to force Struggle.  Not only  does this severely  limit the opponent's raw offensive power, but it  also allows me to set  up on super-effective attacks.  Swords Dancing  three times on a Heatran  is quite satisfying.  Simply controlling the  opponent's move allows me  to avoid all kinds of annoyances such as stat  drops and secondary status  effects.  This allows me to set up quickly  and effectively, regardless  of the opposing Pokemon.  
Despite these qualities, this team has  some shortcomings.  Foremost on  this list is Dusknoir's speed.  Even  with a Choice Scarf, my paranormal  radio fails to outpace the majority  of Battle Tower Pokemon.  When so  often moving second, I risk being  haxxed before Dusknoir even gets a  chance to Trick.  My team doesn't  have a great chance of winning when  robbed of Dusknoir right off the  bat.  Scizor's setup can also be  threatened by Critical Hits; even  Struggle is capable of using the  Tower's trump card.  Heatran has pulled  me through some messes, but  bringing me back from 1-3 is not something  she is consistently able to  do.  
I enjoyed using this team, but it failed (and I failed) to produce the  streaks I was looking for.  While plenty of my losses were due to stupid  mistakes or hax, plenty of them happened simply because my team wasn't  constructed well enough, which was disappointing.
Dusknoir (FRAUD) @ Choice Scarf
Male, Bold, Pressure
252 HP / 116 Defense / 116 Special Defense / 20 Speed
152 / 120 / 187 / 76 / 173 / 65
Trick / Grudge / Disable / Rest
Feraligatr (CHAW) @ Salac Berry
Male, Jolly, Torrent
252 Attack / 4 Defense / 252 Speed
160 / 157 / 121 / 89 / 103 / 143
Waterfall / Outrage / Substitute / Swords Dance
Umbreon (VILYA) @ Leftovers
Male, Impish, Synchronize, Shiny
252 HP / 232 Defense / 36 Special Defense
202 / 85 / 176 / 64 / 154 /  85
Payback / Curse / Protect / Wish
Some frustrating losses led me to rethink my team.  I decided to take  advantage of the relatively predictable amount of damage output from  Struggle.  A pinch sweeper is a good way to capitalize on opponents that  often bring me to around 20% HP.  Fully set up, Feraligatr only  has  trouble with the following 10 Pokemon: Linoone 2, Porygon-Z 2,  Slowbro  2, Suicune 3, Cloyster 2, Unaware Bibarel 2, Tangrowth 1-4.  Feraligatr  proved more offensively impressive than Scizor.  
I was also quite happy with Umbreon.  Originally intended to beat  Pokemon Dusknoir couldn't handle, it ended up performing its fair share  of sweeps.  Critical hits happened as often as I expected them to;  despite this, Umbreon's immense bulk kept it alive.  Unfortunately,  pitiful offensive power and an EV spread unfit for this purpose kept 
Vilya  from being truly successful (cookie for the reference on that one).
As you, no doubt, suspected, this team flopped quite spectacularly,  never getting past 80.  The "pinch berry" theory proved quite finicky  and frustrating.  Even considering Feraligatr's defensive prowess, he  returned completely unable to function without Dusknoir.  Even minor hax  saddled this team with a loss.  Despite how sexy it looked, Dusknoir /  Feraligatr / Umbreon was not as viable as I had hoped.  I took a step in  the wrong direction, and it didn't pay off.  
I plan to revisit a Trick /  Struggle strategy in the future.  There are  some faster (if frailer)  Grudge users out there.  My next endeavor,  however, will be a standard  Trick team.  
I have come to one  conclusion; hax is inevitable.  Of course, I've known  this since I first attempted the Tower.  The problem is, I haven't been  implementing this knowledge to its full extent.  I always knew to use  Flamethrower over Fire Blast in an environment where streaks matter.   What I still need to deal with is the fact that Ice Beam Freezes, Flame  Body Burns, and Brightpowder misses are all inevitable, but  conquerable.  While that perfect combination of opposing Pokemon and hax  is 
going to happen, I can postpone this event by taking such  things into account.  For example, Jumpman has found a way to  incorporate accuracy increases, immunity to Critical hits, and team  synergy into twelve moveslots.  It's not enough that I use 100% accurate  moves, I need to deal with things the opposition brings to the table as  well.
Which brings me to my current project: Lapras.  A couple of critical  hits followed by freezes led me to seek out a teammate immune to both.   Because the Battle Tower imposes pessimism, I initially rejected the  hope that one of my favourite Pokemon would be uniquely viable in the  Battle Tower.  Since scouting it more thoroughly, I have come to believe  that Lapras is an excellent Tower 'mon, using him is certainly not a  pipe dream.  With the very real and consistent possibility of six Curses  under its belt, Lapras literally cannot be ohko'd by any Pokemon except  for the lucky few with ohko moves.  Needless to say, I was pleased when  I saw that another person came to the same conclusion.
	
		
			
				Jumpman16 said:
			
		
	
	
		
		
			I've  been theorymonning a Lapras for the third slot on a team like this  to soak up Ice Beams and prevent freezing, and I think Lapras@Leftovers:  Waterfall/Ice Shard/Curse/Sub, 252HP/4Atk/252SpD, Shell Armor is the  best set.  Things like Charizard FT, Infernape FT, and Gengar Shadow  ball aren't even guaranteed to break Lapras's Sub (barely but still),  and you can forget about physical attacks on 237HP and 400Def stats that  make even Lv100 252HP/Def+ Dusknoir jealous (probably mainly because  Lapras can actually use Curse correctly lol).  Adding Shell Armor to all  this makes Lapras seem really awesome on paper, but it would probably  be really annoyed by electrics and fighters since +6 Ice Shard doesn't  kill a whole lot of pokemon.  Going with Avalanche over Sub to triple  the Ice damage (Avalanche doesn't get 120 BP if the foe hits your Sub)  seems appetizing but risky even with Lapras's Shell Armor inability to  be OHKOed by literally any move (even Raikou Wise Glasses Thunder  [71-87%]).  This is because of dumb Paralysis stuff on stuff I have to  Waterfall, and Focus Sash/Counter garbage—seven pokes have this combo  including mega idiot Gliscor who takes SE damage from both WF and IS and  would OHKO with Counter then outspeed Drapion.  Otherwise, against  sash/counter pokemon like Breloom and Weavile, I can use the NVE move  first then use the normal- or super effective move, essentially  employing a rather *puts on sunglasses*... "effective" strategy  (Phiddlesticks that was for you!).
 
This would make going without Sub on a sweeper poke in the BT actually a  somewhat worry-free proposition for the first time, at least on paper,  but there's probably some dumb stuff that will be able to kill Shell  Armor +6Def Lapras with 237HP/161SpD.  In a cursory look at what  possibly could, Venusaur is OHKOed by Ice Shard every time, and while  Meganium 3 is not (78-93%), it is incapable of killing 100% HP lapras  even with Overgrow Leaf Storm, which does 200-236HP, and I find that  kind of hilarious (if I weren't at 100% HP I'd just switch to Drapion  probably or just Waterfall it first with the same "effective" strat I'd  use for some of the Counter/Sash pokes).
		
		
	 
I was planning  to make this post later in the summer, (after I had actually  accomplished something with what is now just a team in theory) but I  didn't want to miss responding to this.  Lapras as a hax-"immune"  Pokemon for incredibly lengthy streaks sounds fun to me.  
As for  
"dumb stuff that could KO this Lapras", not even Adamant Life  Orb Head Smash Rampardos can do 70% to the plesiosaur on the  physical side.  Able to survive a Leaf Storm from Roserade  (theoretically; normally you'd just Shard it for super effective  damage), nothing's touching Lapras on either side of the spectrum.  It  is important to remember that few Tower Pokemon have stat boosting items  such as Choice Specs.  
What I worry about is the offense.  8/2  Ice Shard will get rid of most sweepers, but bulky Pokemon, or those  that resist Ice might give Lapras trouble.  You were suggesting  Avalanche over Substitute (I assume partly because that's pretty  ballsy), but I was actually thinking of replacing Waterfall.  I'd have  to go through and figure out the exact difference, but only two Pokemon  (Heatran and Empoleon) resist Ice 4x.  The higher power helps out  against water types, and bulkier neutral Pokemon like Cresselia.  Fire  types are almost a non-issue in this circumstance; Avalanche followed up  by Ice Shard deals with even Intimidate Arcanine equally as well as  Waterfall.  Even if Avalanche isn't worth it over Waterfall, I'd have a  hard time giving up my Substitute, (see the avatar) especially one that  can withstand STAB attacks.  What I worry about are Pokemon like Lanturn, who can take my attacks quite well, and hax me with moves like Discharge.  
Latias  (Flow) @ Choice Scarf
Female, Timid, Levitate
252 HP / 182  Defense / 76 Speed
187 / 90 / 133 / 130 / 150 / 154
Trick /  Thunder Wave / Charm / Recover
Drapion (Doopliss) @  Black Sludge
Male, Careful, Battle Armor
252 HP / 56  Defense / 196 Special Defense / 4 Speed
177 / 110 / 137 / 72 / 132 /  116
Crunch / Substitute / Acupressure / Rest
Lapras (Hymn) @  Leftovers
Male, Careful, Shell Armor
252 HP / 4 Attack /  252 Special Defense
237 / 106 / 100 / 94 / 161 / 80
Ice Shard / Waterfall / Curse / Substitute
What do you  think?  I'm going to attempt it.
...right after finals, that is.   :(