Just got back from another long layoff from pokemon, so please excuse the occasional errors. (p.s. haven't scrolled the entire thread ._.)
On paper, this all looks good. ttar + rhyperior will most probably be whored as 1.5 * Sdef augments his trait very well, helping cover that horrendous SDef. However, I think it would be best to reserve all judement until we actually start battling (I'm assuming Competitor is near completion?).
This reminds me of when CBers were very popular in ADV - predict, or you die. Which is why Substitute on it would be very effective, it prevents you from getting screwed if you predict wrongly.
Granted, this thing still scares the shit out of me, alongside sala and company. A successful agilipass would prolly be gg though...
Aside from that... Nothing much that probably hasn't been said already. This will definitely be a threat and if the current assumptions are correct every team will have to be carefully planned out as something like 4-6 of the pokes cannot allow this monster to switch in.
Snorlax, which usually sports ~300 att iirc does shit with earthquake, and, being slower, is just asking to be switched on by this guy. Suicune/Swampert/bulky water will be worn down by constant EQs on the switch (much like cbmence with hp fly back then) and I don't think pressure from cune, or cune + clops for that matter will be enough.
Gamefreak's biggest mistake since Wobba? or a strong, OU pokemon (top-tier or not) way overblown by hype? Only time will tell.