A 30 year old male presented with episodes of near syncope with dizziness, palpitations, chest tightness, and left arm paresthesias. Upon presentation, his vitals were normal. Initial imaging of a chest radiograph showed an enlarged cardiac silhouette and a follow-up chest CT demonstrated a 10 cm cystic mass in the anterior mediastinum concerning for a giant pericardial cyst. Echocardiogram was performed which showed a normal ejection fraction, no valvular abnormalities, and a trivial pericardial effusion. A CT-guided drainage was performed with 440mL of fluid removed and shrinkage of the cyst to 27x63mm. The aspirate was loaded with leukocytes without organisms identified. The following day, the cyst recollected to 85x69mm. Repeat CT-guided drainage was attempted however was unsuccessful due to right pneumothorax. After resolution of the pneumothorax, he was asymptomatic prompting discharge with close outpatient follow-up. Outpatient imaging demonstrated increased size of the pericardial cyst to 11 cm in diameter. A third drainage via CT-guidance was attempted however only minimal fluid was able to be drained. As the patient remained asymptomatic, it was recommended the patient have repeat imaging in 6 months and monitor for symptoms. Pericardial cysts are relatively rare and comprise 7% of mediastinal masses. They originate from failed fusion of the mesenchymal lacunae that form the pericardial coelom. Pericardial cysts typically range from 1 to 5 cm in diameter, with those over 10cm being termed 'giant pericardial cysts'. Most cysts are asymptomatic, although if symptoms do occur they are generally in response to mass effect and compression of local structures, such as shortness of breath and chest discomfort. If a patient remains asymptomatic, conservative management with serial imaging is recommended. However, if a patient becomes symptomatic or develops complications, surgical management via a pericardectomy or percutaneous aspiration is recommended.