TOPSIS is one of the ranking methods a challenge creator can choose. Instead of just averaging scores, it ranks each submission by how close it is to an ideal profile (the best score on every criterion) relative to how close it is to the worst-case profile — a submission that's consistently strong across all criteria ranks higher than one with a few very high scores and a few very low ones, even if their simple averages are similar.
You don't need to do anything differently as a judge if a challenge uses TOPSIS — you still score each criterion the same way. TOPSIS only changes how the platform combines everyone's scores afterward.
