Worm

At the start of your turn, roll a d20:
(1) Teleport to space 1.
(2-4) End your turn.
(5-7) Gain a -1 counter.
(8-10) Roll a d4 instead of a d6.
(11-13) Roll a d8 instead of a d6.
(14-16) Roll a d10 instead of a d6.
(17-19) Take an extra turn after this one.
(20) Teleport to the finish.