arrow tremors roy cw 1 stephen amell colton haynes 'Arrow' photos: The training of Roy Harper in 'Tremors'“Arrow” has a Roy Harper problem these days. The teenage vigilante-in-training can’t really know the secret of the Arrow — since he’s dating Oliver’s little sister — but mirakuru means that an untrained Roy is a dangerous Roy.

Thus, training begins in the upcoming episode, “Tremors.”

Roy (Colton Haynes) isn’t likely to be a good, patient student. This could be a problem when Oliver (Stephen Amell) has the young man do that slapping-water exercise from martial arts.

arrow tremors roy cw 2 colton haynes stephen amell 'Arrow' photos: The training of Roy Harper in 'Tremors'In fact, Roy might just break the bowl.

arrow tremors roy cw 3 colton haynes 'Arrow' photos: The training of Roy Harper in 'Tremors'Moving on to fighting skills, the Arrow shows his protege how it’s done.

arrow tremors roy cw 4 stephen amell colton haynes 'Arrow' photos: The training of Roy Harper in 'Tremors'Roy seems to be getting it …

arrow tremors roy cw 5 colton haynes 'Arrow' photos: The training of Roy Harper in 'Tremors'Until he breaks this piece of equipment as well.

arrow tremors roy cw 6 colton haynes 'Arrow' photos: The training of Roy Harper in 'Tremors'Training could end up being very, very difficult.

“Tremors” airs Wednesday, Jan. 29 at 8 p.m. ET on The CW.