15 of the 22 strategies in the original tournament were NiceBots, meaning that they sought mutual cooperation until the endgame (formally, they always cooperated for the first 90 rounds against any strategy that cooperated with it for the first 90 rounds). They were mostly tit-for-tat with some combination of vengeance, forgiveness, and endgame defection (Win-stay lose-shift was the one exception).

In the 100-round evolutionary tournament, 15/22 bots survived until the end: the 15 NiceBots all survived and the 7 non-Nice bots all went extinct. In the larger (33-bot, 100-round) tournament, there were 2 exceptions to this pattern. 5 of the 6 new NiceBots survived (C5 went extinct) and 1 of the 5 non-Nice bots survived (C10, which played Nice for the first 84 rounds). [Edited to include C3 among the non-Nice.]

Nice: ABCDEFGHIJKORST C2,4,5,6,9,11 (only C5 went extinct)
Not Nice: LMNPQUZ C1,3,7,8,10 (only C10 survived)

In games between two NiceBots only endgame strategy matters, which means that endgame strategy became increasingly important (and differences in general rules became less important) as the non-Nice bots left the population. Another option for separating general rules from endgame play would be to shorten the game to 90 or 95 rounds (but don't tell the bots) so that we can see what would happen without the endgame.