Hey all,It's been three months since UU went official, so that means it's time for a usage-based tier update.For those new to our system, how our tiers work is that they're primarily based on usage (the names of the tiers, OU, UU, RU and NU, literally mean "versed," "ndersed," "arelysed" and "eversed"): Pokemon that are used heavily in the tier above get banned from the tiers below. The cutoff for each tier is the point at which you're more than 50% likely to encounter that Pokemon at least once in a given day of playing, if you play 20 battles a day. For those that don't feel like doing the math themselves, that number is approximately 3.41%. So that means if a Pokemon is used on 4% of OU teams, it's considered OU and is banned from UU, RU and NU.This 3.41% number is based on stats weighted over the previous three months , with 5/6 of the weighting from the last month, 1/8 from the month before that, and 1/24 from the month before that (ratio of 20-3-1).Finally, for those who are familiar with how we calculate usage stats know, we weight our stats based on player skill rating , and we're calculating stats using a baseline of 1695 for OU and 1630 for UU and RU (this is different from last time ). To eliminate some numerical anomalies, we're also throwing out teams where the player'sis greater than 100 (meaning they've had less than ~5 battles under their alt). In the next few days, I'll be making a thread discussing this decision in more detail.On top of the usage-based tiers we also have "borderline" or "BL" tiers, which are essentially Ubers banlists for the lower tiers. These lists ban Pokemon that aren't used enough in the higher tiers but are too overpowered for the lower ones. BL banlists are not subject to usage stats, except a BL Pokemon can, of course, move into a higher tier (from BL to OU, from BL2 to UU).Also note that a Pokemon cannot drop more than one tier per update cycle. Say no one used Charizard in OU for the next three months. That would drop it down to UU, even though it had no usage in UU for that period (how could it? It was OU).I think that covers everything! So without further ado, let me get to the tiers.Note that I'm publishing these before I publish May's stats. Those are still being generated, but I decided to make sure the usage-based tiers got top priority.