UMVC3/Strategy/Assist Types

As is common in the social sciences, following the 80-20 rule, about 20% of the assist moves in this game (or perhaps 33%, given 3 assist types per character) do about 80% of the work for the teams they’re used on. Most characters have one clear winner among their assist types for winning matches, and some characters have a second assist that proves conditionally useful but that requires thought to use effectively. For instance,

• beams can cover the screen
• extra assists can build meter
• OTG assists can sustain long combos
• Powered-up/Mode Change’d assists can do more damage for a non-active character than they really maybe ought to.
• Low-hitting assists create easy unblockable openers
• Jumping assists can avoid ground attacks or attack overhead
• Certain assists have autoblock or invincibility properties

A character should rarely be selected exclusively for her assist. The assists generally correlate to the character’s playstyle, and the characters you choose should contribute to your intended core playstyle; thus, the assist choices become a natural extension of the choices already made. Carts and horses generally work best when placed in the traditional order.
Of course, there are exceptions, and certain characters on the roster have special needs that can often be filled by highly unorthodox assists (such as a 3C Liberation assist from Dormammu, to ground prey for MODOK’s aerial assault). Just get the team down first— lay rocks, then fill in the gaps with sand.