Argumentum ad hominem, or excessive personal attacks that often include childish name-calling and personal put-downs, more so than other debaters
Proof by authority, or highlighting their own academic credentials or those of their allies in support of their theories. An academic credential can include anything from a publishing credit (especially in a "peer-reviewed" journal) to a degree to a particular academic appointment. However, Ben Stein (Expelled: No Intelligence Allowed) shows that evolutionists add this twist: they systematically deny to others, whenever they can, any opportunity to acquire similar credentials.
Inordinate attempt to demonize the other side, as in overuse of the term creationist and fundamentalist. The latter example includes the attempt to show that Christian fundamentalists are morally equivalent to Muslim fundamentalists, whether in their extreme rejection of modernity or in their practice and advocacy of terrorism.
An astounding lack of understanding -- or denial -- of how most great scientists and mathematicians either rejected evolution or were silent about it
An equal lack of understanding, or denial, that most of the greatest scientists in the Western world asserted the reality of creation and the Great Flood prior to the Enlightenment, or else a denial that their scientific achievements (including those of Sir Isaac Newton!) matter today.