He has won three Nicky Rackard Cups and represented (and captained) Ireland against Scotland in the Shinty-Hurling International Series.
[5] He played on the Setanta team that won the 2022 Ulster Junior Club Hurling Championship.
[11] Cullen won the 2013 Nicky Rackard Cup with Donegal, playing in the final against Roscommon and scoring three points.
[12] He played for Donegal during the 2018 National Hurling League, when the county recorded their first competitive victories over Derry and Down.
[26] He captained the Ireland team for the Abbotstown contest in 2019, and was his county's only representative in that year's squad.
[28] He appeared in a short film on hurling made by a CNN-owned company based in New York and London.