Sitrus allows you to Belly Drum after they they hit you without loosing a turn.
Also, double switching.
Not that Latios can switch into or revenge kill an Azumarill that already set up, talkin' 'bout the other way 'round.
Paralysis is always, ALWAYS beneficial, even on Slowking-speed things, if another option wouldn't defeat the threat in question. It effectively gives all'a their moves, includin' Speed-bypassing priority ones, a 25% chance of missing. If your team doesn't have six turns to stall out a sweeper via Burn/Poison damage since you've only three easily-OHKO'd Pokes left, Paralysis gives you a chance t' win in that situation via fully paralyzed hax. Priority T-wave was the sole reason Thundurus got banned last Generation; if it couldn't revenge kill an opposing non-Ground type threat, it'd be guaranteed to cripple it.
More importantly, if a team doesn't KO Azumarill by the second turn after it Belly Drums, be it by revenge kill or the Poke currently out, they likely already lost. Leftovers recovering more HP overtime than Sitrus is often irrelevant on a sweeper like BDAzumarill, which is meant to setup and sweep quickly.
Choiced Dragons are Azumarill Fodder.
Though this can be avoided if you are careful. (Don't lock yourself into a Dragon move)
The most important thing about Azumarill is not to use it. Ever.
♦ The Fuchsia City Guru ♦
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