Oh, shit. Tim stared in horror at the reaction Knives was having to the gas - under other circumstances it would have been interesting to see just what the differences in how the chemical compound affected Plant biology, but it looked painful and dangerous and was definitely not something he wanted to be seeing right now. He threw a tangle grenade after Joker's retreating form as he stood up, but it was a half-hearted effort that he didn't expect to catch the madman - Knives had just taken priority. Tim had to do something to help him, as fast as possible.

The laughter seemed to indicate that the chemical was reacting similarly to the way it would in humans, at least, and although Tim didn't have any Joker venom antidote on him - not that it could have been guaranteed to work, even if he did - a mild sedative might help relax Knives's muscles and prevent him from dying, or going completely out of control, before Tim could get him to a healer. There was just the question of avoinding the rapidly sprouting blades for long enough to get close and administer it, and Tim was still smarting enough from his fight with Joker that he wasn't exactly moving at top form.

But he had to try anyway.

"Hold on, this'll help. I hope." He said as he pulled out the small hypo and approached, carefully, trying to keep his voice calm even though he was really having trouble avoiding getting himself skewered.