Ironic is a Challenge in the feats catergory.
- Assassinate Kalvin Ritter by drowning him.
- Freeform Training - Already accessible if the mission is bought.
If you have an easier time learning by watching, you can check the video for a walkthrough of the challenge.
Start of by heading towards the left side entrance of the yacht. Climb through the window to access the back area and take out the Mechanic. Put on his disguise and then board the yacht. Walk past the three mechanics and enter the door straight forward to the left of the stairs. In this room you will find Emetic Rat Poison. Head back through the same door and now go up the stairs to reach Deck 01.
Once upstairs, head into the kitchen which is the larger room right infront of you which can be accessed from two sides. Take out the Yacht Crew member who is cooking by the stove and then take his disguise. You can also hide the body in the freezer behind him. Do NOT use the rat poison on the Kitchen Pot. Keep the poison on you and locate the stairs leading to Deck 02.
Once upstairs go to the right (front) side of the boat where the bar is located. Kalvin Ritter will become suspicious of you despite wearing a Yacht Crew uniform so make sure he does not see you. You can blend in at the bar to avoid detection. You will notice that there is a Glass of Red Wine on the table nearest to the bar disk. Ritter will drink from this glass and NOT from the glass on the bar disk itself. Wait for a while and there will be a moment when you can walk up to the drink and apply the rat poison. The only one who is not allowed to see you doing it is Ritter. Since you are wearing a Yacht Crew disguise, no one else will be suspicious of you when you are touching drinks. After putting in the poison, quickly go back and blend in again by the bar. Wait for Ritter to drink from the wine and he will now start to feel sick.
Ritter will now head towards the bathroom. Follow him there, walk into the room behind him and close the door. He will start throwing up in the toilet and you can now stand behind him and kill him by using the drown option. Once you have drowned Ritter in the toilet, then the challenge is completed.