OTHK (Omega Tom Hanks Killer) is used to refer to any character that is capable of defeating Omega Tom Hanks. Because Omega Tom Hanks has no hitboxes and cannot take damage from attacks, methods used by OTHK characters utilize complex workarounds. Most of the time these workarounds take advantage of bugs and glitches in the M.U.G.E.N engine, such as state overflow glitches (null reversals) which force Omega Tom Hanks into a custom state without making contact with an attack. It should be noted that most of these methods will only work in the older versions of M.U.G.E.N, and that many of these methods have been fixed or removed in M.U.G.E.N versions 1.0 and 1.1 due to them only allowing 512 state controllers. However some working methods still exist and work for 1.0/1.1 with the use of a ReversalDef such as shown here. Another working method/tutorial by the author Black Kyurem can be found here.