GRE

Hello Ravivarman,
GRE is required only for US universities and few Canadian Universities. GRE is not at all mandatory for German Universities.
To get into German Universities you need to take IELTS and try to score 6.5 overall with no band less than 6. You may also apply for German Universities with your GATE score.
The top German Universities are :
1) Technische Universitt Mnchen
2) Ludwig-Maximilians-Universitt Mnchen
3) Ruprecht-Karls-Universitt Heidelberg
4) Kit, Karlsruher Institut for Technologie
5) Freie Universitt Berlin
6) Humboldt-Universitt Zu Berlin
7) Universitt Freiburg
8) Georg-August-Universitt Gttingen
9) Rheinisch-Westflische Technische Hochschule Aachen
10) Eberhard Karls Universitt Tbingen
All the best.

The Graduate Record Examination (GRE) is a standardized test that is an admissions requirement for most graduate schools in the United States. Created and administered by the Educational Testing Service (ETS).
The exam aims to measure verbal reasoning, quantitative reasoning, analytical writing, and critical thinking skills that have been acquired over a long period of time and that are not entirely based on any specific field of study outside of the GRE itself.
There are no specific eligibility criteria for GRE. Aspirants can register for the test irrespective of age and qualification. Many graduate schools in the United States require GRE results as part of the admissions process for MS. Different graduate schools have their own criteria for admission and minimum GRE score.