I was Playing the game.... completed 43% and is in this part where Batman must take on Poison Ivy
(TITAN IVY)........ Problem begins as I enter Botanical gardens....... There must be roots blocking my way but screen shows no such roots..... but the path is yet blocked.......... somehow I managed to go furthur...... using map I successfully went to Ivy's Lair...... But as soon as I entered Ivy's Lair the Screen is dark only the moon is visible...... and Batman falls to death........ I don't get it....... What is Problem here????? And what is the solution?????