Riddle
Smash Lord
Smogon's Tiers
Ubers
Ubers is essentially a banlist from OU. Basically if the people at Smogon believe that a pokemon may be too overpowered to be in OU then they hold a test and then vote on it. If the motion passes than that pokemon is banished to Ubers and no longer allowed in OU. How good a pokemon does in Ubers is irrelevant to Ubers status. Ubers pokemon are only allowed in the Ubers tier.
http://www.smogon.com/dp/tiers/uber
OverUsed
OU is a tier that is based on usage. On the Smogon University server of Shoddy Battle, data is collected about how often certain pokemon are used. Every couple of months the stats are looked at and a cut-off is agreed upon and the top pokemon are considered OU and banned from UU play. Viability in any tier is not relevant to OU status. If Magikarp is used enough on the standard ladder then it will become OU. OU pokemon are only allowed in OU and Ubers.
http://www.smogon.com/dp/tiers/OU
BorderLine
BorderLine is exactly the same as Ubers but its a banlist for UU instead of OU. Overpowered UU pokemon are tested and if they are determined to be too good then they are banned from UU and put into BL. OU viability is irrelevant to BL. BL pokemon are only allowed in OU and Ubers.
http://www.smogon.com/dp/tiers/uber
UnderUsed
UU is also a tier based on usage. Data is gathered from smogon university's underused ladder and if pokemon are used enough on the ladder than they become UU and are not allowed to be used in NU. Viability or opinions on the abilities of the pokemon are irrelevant. UU pokemon are allowed in UU, OU, and Ubers.
http://www.smogon.com/dp/tiers/uu
NeverUsed
Anything that is allowed in UU, but not used enough on the UnderUsed ladder to be considered UU is considered NU. This is the largest tier and is ONLY based on usage in UU, NOT usage in NU. Again, this is not based on viability, simply usage. NU pokemon can be used in any tier. NU pokemon are allowed in NU, UU, OU, and Ubers.
http://www.smogon.com/dp/tiers/nu
Little Cup
Any pokemon that can come from an egg and is the lowest form of an evolutionary chain is in LC. However, there are 7 Little Cup Ubers who can not be used in Little Cup. These are:
Scyther
Yanma
Meditite
Tangela
Sneasel
Misdreavus
Murkrow
Standard Rules
Sleep clause:
You can't use sleep inducing moves on an opponent's Pokémon when there's another Pokémon on his/her team asleep. Yawn can't be used to PseudoHaze (make opponent switch) when there's another Pokémon asleep caused by you. When the asleep Pokémon awakens or faints, you're free to make another Pokémon of his/her team asleep. Sleep caused by Effect Spore or Rest are excluded from Sleep Clause.
Species clause:
You can't use two of the same Pokémon in a team. I.E. 2 Scizors.
Evasion clause:
You can't use moves that increases your evasion. I.E. Double Team and Minimize.
Self-KO clause:
This clause covers two things. First, when you and your opponent have only one Pokémon left, if you use Explosion or Self-Destruct, you automatically lose. Also, if you use Destiny Bond, with your last Pokémon, and your opponents last Pokémon faints you, you still lose. This clause was made to stop matches from ending in a tie. Recoil moves (Brave Bird, Double-edge, etc.), however, are excluded from this rule.
OHKO clause:
You are strictly prohibited of using OHKO moves. They are Guillotine, Horn Drill, Fissure and Sheer Cold.
No Hacks:
You cannot use Pokemon with illegal moves or stats (999 in all stats or something ridiculous). Legal Pokesav is fine.
Ubers
Ubers is essentially a banlist from OU. Basically if the people at Smogon believe that a pokemon may be too overpowered to be in OU then they hold a test and then vote on it. If the motion passes than that pokemon is banished to Ubers and no longer allowed in OU. How good a pokemon does in Ubers is irrelevant to Ubers status. Ubers pokemon are only allowed in the Ubers tier.
http://www.smogon.com/dp/tiers/uber
OverUsed
OU is a tier that is based on usage. On the Smogon University server of Shoddy Battle, data is collected about how often certain pokemon are used. Every couple of months the stats are looked at and a cut-off is agreed upon and the top pokemon are considered OU and banned from UU play. Viability in any tier is not relevant to OU status. If Magikarp is used enough on the standard ladder then it will become OU. OU pokemon are only allowed in OU and Ubers.
http://www.smogon.com/dp/tiers/OU
BorderLine
BorderLine is exactly the same as Ubers but its a banlist for UU instead of OU. Overpowered UU pokemon are tested and if they are determined to be too good then they are banned from UU and put into BL. OU viability is irrelevant to BL. BL pokemon are only allowed in OU and Ubers.
http://www.smogon.com/dp/tiers/uber
UnderUsed
UU is also a tier based on usage. Data is gathered from smogon university's underused ladder and if pokemon are used enough on the ladder than they become UU and are not allowed to be used in NU. Viability or opinions on the abilities of the pokemon are irrelevant. UU pokemon are allowed in UU, OU, and Ubers.
http://www.smogon.com/dp/tiers/uu
NeverUsed
Anything that is allowed in UU, but not used enough on the UnderUsed ladder to be considered UU is considered NU. This is the largest tier and is ONLY based on usage in UU, NOT usage in NU. Again, this is not based on viability, simply usage. NU pokemon can be used in any tier. NU pokemon are allowed in NU, UU, OU, and Ubers.
http://www.smogon.com/dp/tiers/nu
Little Cup
Any pokemon that can come from an egg and is the lowest form of an evolutionary chain is in LC. However, there are 7 Little Cup Ubers who can not be used in Little Cup. These are:
Scyther
Yanma
Meditite
Tangela
Sneasel
Misdreavus
Murkrow
Standard Rules
Sleep clause:
You can't use sleep inducing moves on an opponent's Pokémon when there's another Pokémon on his/her team asleep. Yawn can't be used to PseudoHaze (make opponent switch) when there's another Pokémon asleep caused by you. When the asleep Pokémon awakens or faints, you're free to make another Pokémon of his/her team asleep. Sleep caused by Effect Spore or Rest are excluded from Sleep Clause.
Species clause:
You can't use two of the same Pokémon in a team. I.E. 2 Scizors.
Evasion clause:
You can't use moves that increases your evasion. I.E. Double Team and Minimize.
Self-KO clause:
This clause covers two things. First, when you and your opponent have only one Pokémon left, if you use Explosion or Self-Destruct, you automatically lose. Also, if you use Destiny Bond, with your last Pokémon, and your opponents last Pokémon faints you, you still lose. This clause was made to stop matches from ending in a tie. Recoil moves (Brave Bird, Double-edge, etc.), however, are excluded from this rule.
OHKO clause:
You are strictly prohibited of using OHKO moves. They are Guillotine, Horn Drill, Fissure and Sheer Cold.
No Hacks:
You cannot use Pokemon with illegal moves or stats (999 in all stats or something ridiculous). Legal Pokesav is fine.